|District of Columbia|
(English: Justice for All)
|Anthem: "Our Nation's Capital" |
Latitude and Longitude:
|Home Rule Act||1973|
|Named for||George Washington, Christopher Columbus|
|• Mayor||Muriel Bowser ( D)|
|• D.C. Council|
|• U.S. House||
Eleanor Holmes Norton (D),|
|• Federal capital city and federal district||68.34 sq mi (177.0 km2)|
|• Land||61.05 sq mi (158.1 km2)|
|• Water||7.29 sq mi (18.9 km2)|
|Highest elevation||409 ft (125 m)|
|Lowest elevation||0 ft (0 m)|
|• Federal capital city and federal district||705,749|
|• Rank||20th, U.S. as of 2018 [update]|
|• Density||11,506/sq mi (4,442/km2)|
|• Metro||6,216,589 ( 6th, U.S.)|
|• CSA||9,665,892 ( 4th, U.S.)|
|Demonym(s)||Washingtonian  |
|Time zone||UTC−5 ( EST)|
|• Summer ( DST)||UTC−4 ( EDT)|
|Washington, D.C. state symbols|
|Flower||American Beauty rose|
|State route marker|
Released in 2009
|Lists of United States state symbols|
Washington, D.C., formally the District of Columbia and also known as D.C. or Washington, is the capital city of the United States of America.  Founded after the American Revolution as the seat of government of the newly independent country, Washington was named after George Washington, the first president of the United States and a Founding Father.  As the seat of the United States federal government and several international organizations, Washington is an important world political capital.  Located on the Potomac River bordering Maryland and Virginia, the city is one of the most visited cities in the United States, with more than 20 million visitors annually.  
The signing of the Residence Act on July 16, 1790, approved the creation of a capital district located along the Potomac River near the country's East Coast. The U.S. Constitution provided for a federal district under the exclusive jurisdiction of the U.S. Congress, and the District is therefore not a part of any U.S. state. The states of Maryland and Virginia each donated land to form the federal district, which included the pre-existing settlements of Georgetown and Alexandria. The City of Washington was founded in 1791 to serve as the new national capital. In 1846, Congress returned the land originally ceded by Virginia, including the city of Alexandria; in 1871, it created a single municipal government for the remaining portion of the District.
Washington had an estimated population of 705,749 as of July 2019 [update],  making it the 20th most populous city in the United States. Commuters from the surrounding Maryland and Virginia suburbs raise the city's daytime population to more than one million during the workweek.  Washington's metropolitan area, the country's sixth largest (including parts of Maryland, Virginia and West Virginia), had a 2017 estimated population of 6.2 million residents. 
The three branches of the U.S. federal government are centered in the District: Congress (legislative), the president (executive), and the Supreme Court (judicial). Washington is home to many national monuments and museums, primarily situated on or around the National Mall. The city hosts 177 foreign embassies as well as the headquarters of many international organizations, trade unions, non-profits, lobbying groups, and professional associations, including the World Bank Group, the International Monetary Fund (IMF), the Organization of American States, AARP, the National Geographic Society, the Human Rights Campaign, the International Finance Corporation, and the American Red Cross.
A locally elected mayor and a 13‑member council have governed the District since 1973. However, Congress maintains supreme authority over the city and may overturn local laws. D.C. residents elect a non-voting, at-large congressional delegate to the House of Representatives, but the District has no representation in the Senate. District voters choose three presidential electors in accordance with the Twenty-third Amendment to the United States Constitution, ratified in 1961.
Various tribes of the Algonquian-speaking Piscataway people (also known as the Conoy) inhabited the lands around the Potomac River when Europeans first visited the area in the early 17th century. One group known as the Nacotchtank (also called the Nacostines by Catholic missionaries) maintained settlements around the Anacostia River within the present-day District of Columbia. Conflicts with European colonists and neighboring tribes forced the relocation of the Piscataway people, some of whom established a new settlement in 1699 near Point of Rocks, Maryland. 
In his Federalist No. 43, published January 23, 1788, James Madison argued that the new federal government would need authority over a national capital to provide for its own maintenance and safety.  Five years earlier a band of unpaid soldiers had besieged Congress while its members were meeting in Philadelphia. Known as the Pennsylvania Mutiny of 1783, the event emphasized the need for the national government not to rely on any state for its own security. 
Article One, Section Eight, of the Constitution permits the establishment of a "District (not exceeding ten miles square) as may, by cession of particular states, and the acceptance of Congress, become the seat of the government of the United States".  However, the Constitution does not specify a location for the capital. In what is now known as the Compromise of 1790, Madison, Alexander Hamilton, and Thomas Jefferson came to an agreement that the federal government would pay each state's remaining Revolutionary War debts in exchange for establishing the new national capital in the southern United States.  [a]
On July 9, 1790, Congress passed the Residence Act, which approved the creation of a national capital on the Potomac River. The exact location was to be selected by President George Washington, who signed the bill into law on July 16. Formed from land donated by the states of Maryland and Virginia, the initial shape of the federal district was a square measuring 10 miles (16 km) on each side, totaling 100 square miles (259 km2).  [b]
Two pre-existing settlements were included in the territory: the port of Georgetown, Maryland, founded in 1751,  and the city of Alexandria, Virginia, founded in 1749.  During 1791–92, a team under Andrew Ellicott, including Ellicott's brothers Joseph and Benjamin, surveyed the borders of the federal district and placed boundary stones at every mile point.  Many of the stones are still standing. 
A new federal city was then constructed on the north bank of the Potomac, to the east of Georgetown. On September 9, 1791, the three commissioners overseeing the capital's construction named the city in honor of President Washington. The federal district was named Columbia (a feminine form of "Columbus"), which was a poetic name for the United States commonly in use at that time.   Congress held its first session in Washington on November 17, 1800.  
Congress passed the District of Columbia Organic Act of 1801 which officially organized the District and placed the entire territory under the exclusive control of the federal government. Further, the unincorporated area within the District was organized into two counties: the County of Washington to the east of the Potomac and the County of Alexandria to the west.  After the passage of this Act, citizens living in the District were no longer considered residents of Maryland or Virginia, which therefore ended their representation in Congress. 
Burning during the War of 1812
On August 24–25, 1814, in a raid known as the Burning of Washington, British forces invaded the capital during the War of 1812. The Capitol, Treasury, and White House were burned and gutted during the attack.  Most government buildings were repaired quickly; however, the Capitol was largely under construction at the time and was not completed in its current form until 1868. 
Retrocession and the Civil War
In the 1830s, the District's southern territory of Alexandria went into economic decline partly due to neglect by Congress.  The city of Alexandria was a major market in the American slave trade, and pro-slavery residents feared that abolitionists in Congress would end slavery in the District, further depressing the economy. Alexandria's citizens petitioned Virginia to take back the land it had donated to form the District, through a process known as retrocession. 
The Virginia General Assembly voted in February 1846 to accept the return of Alexandria and on July 9, 1846, Congress agreed to return all the territory that had been ceded by Virginia. Therefore, the District's current area consists only of the portion originally donated by Maryland.  Confirming the fears of pro-slavery Alexandrians, the Compromise of 1850 outlawed the slave trade in the District, although not slavery itself. 
The outbreak of the American Civil War in 1861 led to the expansion of the federal government and notable growth in the District's population, including a large influx of freed slaves.  President Abraham Lincoln signed the Compensated Emancipation Act in 1862, which ended slavery in the District of Columbia and freed about 3,100 enslaved persons, nine months prior to the Emancipation Proclamation.  In 1868, Congress granted the District's African American male residents the right to vote in municipal elections. 
Growth and redevelopment
By 1870, the District's population had grown 75% from the previous census to nearly 132,000 residents.  Despite the city's growth, Washington still had dirt roads and lacked basic sanitation. Some members of Congress suggested moving the capital further west, but President Ulysses S. Grant refused to consider such a proposal. 
Congress passed the Organic Act of 1871, which repealed the individual charters of the cities of Washington and Georgetown, and created a new territorial government for the whole District of Columbia.  President Grant appointed Alexander Robey Shepherd to the position of governor in 1873. Shepherd authorized large-scale projects that greatly modernized the City of Washington, but ultimately bankrupted the District government. In 1874, Congress replaced the territorial government with an appointed three-member Board of Commissioners. 
The city's first motorized streetcars began service in 1888 and generated growth in areas of the District beyond the City of Washington's original boundaries. Washington's urban plan was expanded throughout the District in the following decades.  Georgetown's street grid and other administrative details were formally merged to those of the legal City of Washington in 1895.  However, the city had poor housing conditions and strained public works. The District was the first city in the nation to undergo urban renewal projects as part of the " City Beautiful movement" in the early 1900s. 
Increased federal spending as a result of the New Deal in the 1930s led to the construction of new government buildings, memorials, and museums in the District,  though the chairman of the House Subcommittee on District Appropriations Ross A. Collins from Mississippi justified cuts to funds for welfare and education for local residents, saying that "my constituents wouldn't stand for spending money on niggers." 
Civil rights and home rule era
|1960s Washington DC, 4K from 35mm Kinolibrary|
The Twenty-third Amendment to the United States Constitution was ratified in 1961, granting the District three votes in the Electoral College for the election of president and vice president, but still no voting representation in Congress. 
After the assassination of civil rights leader Dr. Martin Luther King, Jr., on April 4, 1968, riots broke out in the District, primarily in the U Street, 14th Street, 7th Street, and H Street corridors, centers of black residential and commercial areas. The riots raged for three days until more than 13,600 federal troops and D.C. Army National Guardsmen stopped the violence. Many stores and other buildings were burned; rebuilding was not completed until the late 1990s. 
In 1973, Congress enacted the District of Columbia Home Rule Act, providing for an elected mayor and thirteen-member council for the District.  In 1975, Walter Washington became the first elected and first black mayor of the District. 
Washington, D.C. is located in the mid-Atlantic region of the U.S. East Coast. Due to the District of Columbia retrocession, the city has a total area of 68.34 square miles (177.0 km2), of which 61.05 square miles (158.1 km2) is land and 7.29 square miles (18.9 km2) (10.67%) is water.  The District is bordered by Montgomery County, Maryland to the northwest; Prince George's County, Maryland to the east; Arlington County, Virginia to the south; and Alexandria, Virginia to the west.
The south bank of the Potomac River forms the District's border with Virginia and has two major tributaries: the Anacostia River and Rock Creek.  Tiber Creek, a natural watercourse that once passed through the National Mall, was fully enclosed underground during the 1870s.  The creek also formed a portion of the now-filled Washington City Canal, which allowed passage through the city to the Anacostia River from 1815 until the 1850s.  The Chesapeake and Ohio Canal starts in Georgetown and was used during the 19th century to bypass the Little Falls of the Potomac River, located at the northwest edge of Washington at the Atlantic Seaboard fall line. 
The highest natural elevation in the District is 409 feet (125 m) above sea level at Fort Reno Park in upper northwest Washington.  The lowest point is sea level at the Potomac River.  The geographic center of Washington is near the intersection of 4th and L Streets NW.   
The District has 7,464 acres (30.21 km2) of parkland, about 19% of the city's total area and the second-highest percentage among high-density U.S. cities.  This factor contributed to Washington, D.C., being ranked as third in the nation for park access and quality in the 2018 ParkScore ranking of the park systems of the 100 most populous cities in the United States, according to the nonprofit Trust for Public Land. 
The National Park Service manages most of the 9,122 acres (36.92 km2) of city land owned by the U.S. government.  Rock Creek Park is a 1,754-acre (7.10 km2) urban forest in Northwest Washington, which extends 9.3 miles (15.0 km) through a stream valley that bisects the city. Established in 1890, it is the country's fourth-oldest national park and is home to a variety of plant and animal species, including raccoon, deer, owls, and coyotes.  Other National Park Service properties include the C&O Canal National Historical Park, the National Mall and Memorial Parks, Theodore Roosevelt Island, Columbia Island, Fort Dupont Park, Meridian Hill Park, Kenilworth Park and Aquatic Gardens, and Anacostia Park.  The D.C. Department of Parks and Recreation maintains the city's 900 acres (3.6 km2) of athletic fields and playgrounds, 40 swimming pools, and 68 recreation centers.  The U.S. Department of Agriculture operates the 446-acre (1.80 km2) U.S. National Arboretum in Northeast Washington. 
Washington is in the northern part of the humid subtropical climate zone ( Köppen: Cfa).  The Trewartha classification is defined as an oceanic climate (Do).  Winters are usually chilly with light snow, and summers are hot and humid. The District is in plant hardiness zone 8a near downtown, and zone 7b elsewhere in the city, indicating a humid subtropical climate. 
Spring and fall are mild to warm, while winter is chilly with annual snowfall averaging 15.5 inches (39 cm). Winter temperatures average around 38 °F (3 °C) from mid-December to mid-February.  However, winter temperatures in excess of 60 °F (16 °C) are not uncommon. 
Summers are hot and humid with a July daily average of 79.8 °F (26.6 °C) and average daily relative humidity around 66%, which can cause moderate personal discomfort.  The combination of heat and humidity in the summer brings very frequent thunderstorms, some of which occasionally produce tornadoes in the area. 
Blizzards affect Washington on average once every four to six years. The most violent storms are called " nor'easters", which often affect large sections of the East Coast.  From January 27 to January 28, 1922, the city officially received 28 inches (71 cm) of snowfall, the largest snowstorm since official measurements began in 1885.  According to notes kept at the time, the city received between 30 and 36 inches (76 and 91 cm) from a snowstorm in January 1772. 
Hurricanes (or their remnants) occasionally track through the area in late summer and early fall but are often weak by the time they reach Washington, partly due to the city's inland location.  Flooding of the Potomac River, however, caused by a combination of high tide, storm surge, and runoff, has been known to cause extensive property damage in the neighborhood of Georgetown. 
Precipitation occurs throughout the year. 
The highest recorded temperature was 106 °F (41 °C) on August 6, 1918, and on July 20, 1930.  while the lowest recorded temperature was −15 °F (−26 °C) on February 11, 1899, right before the Great Blizzard of 1899.  During a typical year, the city averages about 37 days at or above 90 °F (32 °C) and 64 nights at or below the freezing mark (32 °F or 0 °C).  On average, the first day with a minimum at or below freezing is November 18 and the last day is March 27.  
|Record high °F (°C)||79
|Mean maximum °F (°C)||65.5
|Average high °F (°C)||43.4
|Daily mean °F (°C)||36.0
|Average low °F (°C)||28.6
|Mean minimum °F (°C)||12.9
|Record low °F (°C)||−14
|Average precipitation inches (mm)||2.81
|Average snowfall inches (cm)||5.6
|Average precipitation days (≥ 0.01 in)||9.6||9.0||10.5||10.4||11.1||10.7||10.3||8.2||8.3||7.7||8.6||9.7||114.1|
|Average snowy days (≥ 0.1 in)||3.0||2.4||0.9||0.1||0||0||0||0||0||0||0.2||1.5||8.1|
|Average relative humidity (%)||62.1||60.5||58.6||58.0||64.5||65.8||66.9||69.3||69.7||67.4||64.7||64.1||64.3|
|Mean monthly sunshine hours||144.6||151.8||204.0||228.2||260.5||283.2||280.5||263.1||225.0||203.6||150.2||133.0||2,527.7|
|Mean daily daylight hours||9.8||10.8||12.0||13.3||14.3||14.9||14.6||13.6||12.4||11.2||10.1||9.5||12.2|
|Percent possible sunshine||48||50||55||57||59||64||62||62||60||59||50||45||57|
|Average ultraviolet index||2||3||5||7||8||9||9||8||7||4||3||2||6|
|Source: NOAA (relative humidity and sun 1961−1990)     and Weather Atlas |
Washington, D.C. is a planned city. In 1791, President Washington commissioned Pierre (Peter) Charles L'Enfant, a French-born architect and city planner, to design the new capital. He enlisted Scottish surveyor Alexander Ralston to help lay out the city plan.  The L'Enfant Plan featured broad streets and avenues radiating out from rectangles, providing room for open space and landscaping.  He based his design on plans of cities such as Paris, Amsterdam, Karlsruhe, and Milan that Thomas Jefferson had sent to him.  L'Enfant's design also envisioned a garden-lined "grand avenue" approximately 1 mile (1.6 km) in length and 400 feet (120 m) wide in the area that is now the National Mall.  President Washington dismissed L'Enfant in March 1792 due to conflicts with the three commissioners appointed to supervise the capital's construction. Andrew Ellicott, who had worked with L'Enfant surveying the city, was then tasked with completing the design. Though Ellicott made revisions to the original plans—including changes to some street patterns—L'Enfant is still credited with the overall design of the city. 
By the early 1900s, L'Enfant's vision of a grand national capital had become marred by slums and randomly placed buildings, including a railroad station on the National Mall. Congress formed a special committee charged with beautifying Washington's ceremonial core.  What became known as the McMillan Plan was finalized in 1901 and included re-landscaping the Capitol grounds and the National Mall, clearing slums, and establishing a new citywide park system. The plan is thought to have largely preserved L'Enfant's intended design. 
By law, Washington's skyline is low and sprawling. The federal Height of Buildings Act of 1910 allows buildings that are no taller than the width of the adjacent street, plus 20 feet (6.1 m).  Despite popular belief, no law has ever limited buildings to the height of the United States Capitol Building or the 555-foot (169 m) Washington Monument,  which remains the District's tallest structure. City leaders have criticized the height restriction as a primary reason why the District has limited affordable housing and traffic problems caused by suburban sprawl. 
The District is divided into four quadrants of unequal area: Northwest (NW), Northeast (NE), Southeast (SE), and Southwest (SW). The axes bounding the quadrants radiate from the U.S. Capitol building.  All road names include the quadrant abbreviation to indicate their location and house numbers generally correspond with the number of blocks away from the Capitol. Most streets are set out in a grid pattern with east–west streets named with letters (e.g., C Street SW), north–south streets with numbers (e.g., 4th Street NW), and diagonal avenues, many of which are named after states. 
The City of Washington was bordered by Boundary Street to the north (renamed Florida Avenue in 1890), Rock Creek to the west, and the Anacostia River to the east.   Washington's street grid was extended, where possible, throughout the District starting in 1888.  Georgetown's streets were renamed in 1895.  Some streets are particularly noteworthy, such as Pennsylvania Avenue—which connects the White House to the Capitol, and K Street—which houses the offices of many lobbying groups.  Constitution Avenue and Independence Avenue, located on the north and south sides of the National Mall, respectively, are home to many of Washington's iconic museums, including the Smithsonian institutions, the National Archives Building, and the Newseum. Washington hosts 177 foreign embassies, constituting approximately 297 buildings beyond the more than 1,600 residential properties owned by foreign countries, many of which are on a section of Massachusetts Avenue informally known as Embassy Row. 
The architecture of Washington varies greatly. Six of the top 10 buildings in the American Institute of Architects' 2007 ranking of " America's Favorite Architecture" are in the District of Columbia:  the White House, the Washington National Cathedral, the Thomas Jefferson Memorial, the United States Capitol, the Lincoln Memorial, and the Vietnam Veterans Memorial. The neoclassical, Georgian, gothic, and modern architectural styles are all reflected among those six structures and many other prominent edifices in Washington. Notable exceptions include buildings constructed in the French Second Empire style such as the Eisenhower Executive Office Building. 
Outside downtown Washington, architectural styles are even more varied. Historic buildings are designed primarily in the Queen Anne, Châteauesque, Richardsonian Romanesque, Georgian revival, Beaux-Arts, and a variety of Victorian styles. Rowhouses are especially prominent in areas developed after the Civil War and typically follow Federalist and late Victorian designs.  Georgetown's Old Stone House was built in 1765, making it the oldest-standing original building in the city.  Founded in 1789, Georgetown University features a mix of Romanesque and Gothic Revival architecture.  The Ronald Reagan Building is the largest building in the District with a total area of approximately 3.1 million square feet (288,000 m2). 
|Source:   Note: [e]|
|Demographic profile||2010 ||1990 ||1970 ||1940 |
|— Non-Hispanic whites||34.8%||27.4%||26.5% ||71.4%|
|Black or African American||50.7%||65.8%||71.1%||28.2%|
|Hispanic or Latino (of any race)||9.1%||5.4%||2.1% ||0.1%|
The U.S. Census Bureau estimates that the District's population was 705,749 as of July 2019, an increase of more than 100,000 people since the 2010 United States Census.  This continues a growth trend since 2000, following a half-century of population decline.  The city was the 24th most populous place in the United States as of 2010 [update].  According to data from 2010, commuters from the suburbs increase the District's daytime population to over a million.  If the District were a state it would rank 49th in population, ahead of Vermont and Wyoming. 
The Washington Metropolitan Area, which includes the District and surrounding suburbs, is the sixth-largest metropolitan area in the United States with an estimated six million residents in 2014.  When the Washington area is included with Baltimore and its suburbs, the Baltimore–Washington Metropolitan Area had a population exceeding 9.6 million residents in 2016, the fourth-largest combined statistical area in the country. 
According to 2017 Census Bureau data, the population of Washington, D.C., was 47.1% Black or African American, 45.1% White (36.8% non-Hispanic White), 4.3% Asian, 0.6% American Indian or Alaska Native, and 0.1% Native Hawaiian or Other Pacific Islander. Individuals from two or more races made up 2.7% of the population. Hispanics of any race made up 11.0% of the District's population. 
Washington has had a significant African American population since the city's foundation.  African American residents composed about 30% of the District's total population between 1800 and 1940.  The black population reached a peak of 70% by 1970, but has since steadily declined due to many African Americans moving to the surrounding suburbs. Partly as a result of gentrification, there was a 31.4% increase in the non-Hispanic white population and an 11.5% decrease in the black population between 2000 and 2010.  According to a study by the National Community Reinvestment Coalition, D.C. has experienced more "intense" gentrification than any other American city, with 40% of neighborhoods gentrified. 
About 17% of D.C. residents were age 18 or younger in 2010; lower than the U.S. average of 24%. However, at 34 years old, the District had the lowest median age compared to the 50 states.  As of 2010 [update], there were an estimated 81,734 immigrants living in Washington, D.C.  Major sources of immigration include El Salvador, Vietnam, and Ethiopia, with a concentration of Salvadorans in the Mount Pleasant neighborhood. 
Researchers found that there were 4,822 same-sex couples in the District of Columbia in 2010; about 2% of total households.  Legislation authorizing same-sex marriage passed in 2009, and the District began issuing marriage licenses to same-sex couples in March 2010. 
A 2007 report found that about a third of District residents were functionally illiterate, compared to a national rate of about one in five. This is attributed in part to immigrants who are not proficient in English.  As of 2011 [update], 85% of D.C. residents age 5 and older spoke English at home as a primary language.  Half of residents had at least a four-year college degree in 2006.  In 2017, the median household income in D.C. was $77,649;  also in 2017, D.C. residents had a personal income per capita of $50,832 (higher than any of the 50 states).   However, 19% of residents were below the poverty level in 2005, higher than any state except Mississippi. In 2019, the poverty rate stood at 14.7%.  [f] 
Of the District's population, 17% is Baptist, 13% is Catholic, 6% is evangelical Protestant, 4% is Methodist, 3% is Episcopalian/ Anglican, 3% is Jewish, 2% is Eastern Orthodox, 1% is Pentecostal, 1% is Buddhist, 1% is Adventist, 1% is Lutheran, 1% is Muslim, 1% is Presbyterian, 1% is Mormon, and 1% is Hindu.  [g]
As of 2010 [update], more than 90% of D.C. residents had health insurance coverage, the second-highest rate in the nation. This is due in part to city programs that help provide insurance to low-income individuals who do not qualify for other types of coverage.  A 2009 report found that at least three percent of District residents have HIV or AIDS, which the Centers for Disease Control and Prevention (CDC) characterizes as a "generalized and severe" epidemic. 
|Affiliation||% of Washington, D.C. adult population|
|Historically Black Protestant||23|
|Church of Jesus Christ of Latter-day Saints||1|
|Nothing in particular||14|
|Nothing in particular (religion not important)||9|
|Nothing in particular (religion important)||6|
|Other non-Christian faiths||1|
Crime in Washington, D.C., is concentrated in areas associated with poverty, drug abuse, and gangs. A 2010 study found that 5% percent of city blocks accounted for more than 25% of the District's total crimes. 
The more affluent neighborhoods of Northwest Washington are typically safe, especially in areas with concentrations of government operations, such as Downtown Washington, D.C., Foggy Bottom, Embassy Row, and Penn Quarter, but reports of violent crime increase in poorer neighborhoods generally concentrated in the eastern portion of the city.  Approximately 60,000 residents are ex-convicts. 
In 2012, Washington's annual murder count had dropped to 88, the lowest total since 1961.  The murder rate has since risen from that historic low, though it remains close to half the rate of the early 2000s.  Washington was once described as the "murder capital" of the United States during the early 1990s.  The number of murders peaked in 1991 at 479, but the level of violence then began to decline significantly. 
In 2016, the District's Metropolitan Police Department tallied 135 homicides, a 53% increase from 2012 but a 17% decrease from 2015.  Many neighborhoods such as Columbia Heights and Logan Circle are becoming safer and vibrant. However, incidents of robberies and thefts have remained higher in these areas because of increased nightlife activity and greater numbers of affluent residents.  Even still, citywide reports of both property and violent crimes have declined by nearly half since their most recent highs in the mid-1990s. 
On June 26, 2008, the Supreme Court of the United States held in District of Columbia v. Heller that the city's 1976 handgun ban violated the right to keep and bear arms as protected under the Second Amendment.  However, the ruling does not prohibit all forms of gun control; laws requiring firearm registration remain in place, as does the city's assault weapon ban. 
Washington has a growing, diversified economy with an increasing percentage of professional and business service jobs.  The District's gross state product in 2018-Q2 was $141 billion.  The Washington Metropolitan Area's gross product was $435 billion in 2014, making it the sixth-largest metropolitan economy in the United States.  Between 2009 and 2016, GDP per capita in Washington has consistently ranked on the very top among U.S. states.  In 2016, at $160,472, its GDP per capita is almost three times as high as that of Massachusetts, which was ranked second in the nation.  As of 2011 [update], the Washington Metropolitan Area had an unemployment rate of 6.2%; the second-lowest rate among the 49 largest metro areas in the nation.  The District of Columbia itself had an unemployment rate of 9.8% during the same time period. 
In December 2017, 25% of the employees in Washington, D.C., were employed by a federal governmental agency.   This is thought to immunize Washington, D.C., to national economic downturns because the federal government continues operations even during recessions.  Many organizations such as law firms, defense contractors, civilian contractors, nonprofit organizations, lobbying firms, trade unions, industry trade groups, and professional associations have their headquarters in or near Washington, D.C., in order to be close to the federal government.  The city of Rosslyn, Virginia, located across the Potomac River from D.C., serves as a base of operations for several Fortune 500 companies, due to the building height restrictions in place within the District of Columbia. In 2018, Amazon announced they would build "HQ 2" in the Crystal City neighborhood of Arlington, Virginia. 
Tourism is Washington's second-largest industry. Approximately 18.9 million visitors contributed an estimated $4.8 billion to the local economy in 2012.  The District also hosts nearly 200 foreign embassies and international organizations such as the World Bank, the International Monetary Fund (IMF), the Organization of American States, the Inter-American Development Bank, and the Pan American Health Organization. In 2008, the foreign diplomatic corps in Washington employed about 10,000 people and contributed an estimated $400 million annually to the local economy. 
The District has growing industries not directly related to government, especially in the areas of education, finance, public policy, and scientific research. Georgetown University, George Washington University, Washington Hospital Center, Children's National Medical Center and Howard University are the top five non-government-related employers in the city as of 2009 [update].  According to statistics compiled in 2011, four of the largest 500 companies in the country were headquartered in the District.  In the 2017 Global Financial Centres Index, Washington was ranked as having the 12th most competitive financial center in the world, and fifth most competitive in the United States (after New York City, San Francisco, Chicago, and Boston). 
The National Mall is a large, open park in downtown Washington between the Lincoln Memorial and the United States Capitol. Given its prominence, the mall is often the location of political protests, concerts, festivals, and presidential inaugurations. The Washington Monument and the Jefferson Pier are near the center of the mall, south of the White House. Also on the mall are the National World War II Memorial at the east end of the Lincoln Memorial Reflecting Pool, the Korean War Veterans Memorial, and the Vietnam Veterans Memorial. 
Directly south of the mall, the Tidal Basin features rows of Japanese cherry trees.  The Franklin Delano Roosevelt Memorial, George Mason Memorial, Jefferson Memorial, Martin Luther King Jr. Memorial, and the District of Columbia War Memorial are around the Tidal Basin. 
The National Archives houses thousands of documents important to American history, including the Declaration of Independence, the Constitution, and the Bill of Rights.  Located in three buildings on Capitol Hill, the Library of Congress is the largest library complex in the world with a collection of more than 147 million books, manuscripts, and other materials.  The United States Supreme Court Building was completed in 1935; before then, the court held sessions in the Old Senate Chamber of the Capitol. 
The Smithsonian Institution is an educational foundation chartered by Congress in 1846 that maintains most of the nation's official museums and galleries in Washington, D.C. The U.S. government partially funds the Smithsonian, and its collections are open to the public free of charge.  The Smithsonian's locations had a combined total of 30 million visits in 2013. The most visited museum is the National Museum of Natural History on the National Mall.  Other Smithsonian Institution museums and galleries on the mall are: the National Air and Space Museum; the National Museum of African Art; the National Museum of American History; the National Museum of the American Indian; the Sackler and Freer galleries, which both focus on Asian art and culture; the Hirshhorn Museum and Sculpture Garden; the Arts and Industries Building; the S. Dillon Ripley Center; and the Smithsonian Institution Building (also known as "The Castle"), which serves as the institution's headquarters.  The Smithsonian American Art Museum and the National Portrait Gallery are housed in the Old Patent Office Building, near Washington's Chinatown.  The Renwick Gallery is officially part of the Smithsonian American Art Museum but is in a separate building near the White House. Other Smithsonian museums and galleries include: the Anacostia Community Museum in Southeast Washington; the National Postal Museum near Union Station; and the National Zoo in Woodley Park. 
The National Gallery of Art is on the National Mall near the Capitol and features works of American and European art. The gallery and its collections are owned by the U.S. government but are not a part of the Smithsonian Institution.  The National Building Museum, which occupies the former Pension Building near Judiciary Square, was chartered by Congress and hosts exhibits on architecture, urban planning, and design. 
There are many private art museums in the District of Columbia, which house major collections and exhibits open to the public such as the National Museum of Women in the Arts and The Phillips Collection in Dupont Circle, the first museum of modern art in the United States.  Other private museums in Washington include the Newseum, the O Street Museum Foundation, the International Spy Museum, the National Geographic Society Museum, the Marian Koshland Science Museum and the Museum of the Bible. The United States Holocaust Memorial Museum near the National Mall maintains exhibits, documentation, and artifacts related to the Holocaust. 
Washington, D.C., is a national center for the arts. The John F. Kennedy Center for the Performing Arts is home to the National Symphony Orchestra, the Washington National Opera, and the Washington Ballet. The Kennedy Center Honors are awarded each year to those in the performing arts who have contributed greatly to the cultural life of the United States.  The historic Ford's Theatre, site of the assassination of President Abraham Lincoln, continues to operate as a functioning performance space as well as a museum. 
The Marine Barracks near Capitol Hill houses the United States Marine Band; founded in 1798, it is the country's oldest professional musical organization.  American march composer and Washington-native John Philip Sousa led the Marine Band from 1880 until 1892.  Founded in 1925, the United States Navy Band has its headquarters at the Washington Navy Yard and performs at official events and public concerts around the city.  Washington has a strong local theater tradition. Founded in 1950, Arena Stage achieved national attention and spurred growth in the city's independent theater movement that now includes organizations such as the Shakespeare Theatre Company, Woolly Mammoth Theatre Company, and the Studio Theatre.  Arena Stage opened its newly renovated home in the city's emerging Southwest waterfront area in 2010.  The GALA Hispanic Theatre, now housed in the historic Tivoli Theatre in Columbia Heights, was founded in 1976 and is a National Center for the Latino Performing Arts. 
The U Street Corridor in Northwest D.C., known as "Washington's Black Broadway", is home to institutions like the Howard Theatre, Bohemian Caverns, and the Lincoln Theatre, which hosted music legends such as Washington-native Duke Ellington, John Coltrane, and Miles Davis.  Washington has its own native music genre called go-go; a post-funk, percussion-driven flavor of rhythm and blues that was popularized in the late 1970s by D.C. band leader Chuck Brown. 
The District is an important center for indie culture and music in the United States. The label Dischord Records, formed by Ian MacKaye, frontman of Fugazi, was one of the most crucial independent labels in the genesis of 1980s punk and eventually indie rock in the 1990s.  Modern alternative and indie music venues like The Black Cat and the 9:30 Club bring popular acts to the U Street area. 
Washington is one of 13 cities in the United States with teams from all four major professional men's sports and is home to one major professional women's team. The Washington Wizards (National Basketball Association) and the Washington Capitals (National Hockey League) play at the Capital One Arena in Chinatown. The Washington Mystics (Women's National Basketball Association) play in the St. Elizabeths East Entertainment and Sports Arena. Nationals Park, which opened in Southeast D.C. in 2008, is home to the Washington Nationals (Major League Baseball). D.C. United (Major League Soccer) plays at Audi Field. The Washington Redskins (National Football League) play at FedExField in nearby Landover, Maryland.
Current D.C. teams have won a combined thirteen professional league championships: the Washington Redskins have won five (including three Super Bowls during the 1980s);  D.C. United has won four;  and the Washington Wizards (then the Washington Bullets), Washington Capitals, Washington Mystics and Washington Nationals have each won a single championship.  
Other professional and semi-professional teams in Washington include: DC Defenders ( XFL), Old Glory DC ( Major League Rugby), the Washington Kastles (World TeamTennis); the Washington D.C. Slayers (USA Rugby League); the Baltimore Washington Eagles (U.S. Australian Football League); the D.C. Divas (Independent Women's Football League); and the Potomac Athletic Club RFC (Rugby Super League). The William H.G. FitzGerald Tennis Center in Rock Creek Park hosts the Citi Open. Washington is also home to two major annual marathon races: the Marine Corps Marathon, which is held every autumn, and the Rock 'n' Roll USA Marathon held in the spring. The Marine Corps Marathon began in 1976 and is sometimes called "The People's Marathon" because it is the largest marathon that does not offer prize money to participants. 
The District's four NCAA Division I teams, American Eagles, George Washington Colonials, Georgetown Hoyas and Howard Bison and Lady Bison, have a broad following. The Georgetown Hoyas men's basketball team is the most notable and also plays at the Capital One Arena. From 2008 to 2012, the District hosted an annual college football bowl game at RFK Stadium, called the Military Bowl.  The D.C. area is home to one regional sports television network, Comcast SportsNet (CSN), based in Bethesda, Maryland.
Washington, D.C., is a prominent center for national and international media. The Washington Post, founded in 1877, is the oldest and most-read local daily newspaper in Washington.  "The Post", as it is popularly called, is well known as the newspaper that exposed the Watergate scandal.  It had the sixth-highest readership of all news dailies in the country in 2011.  From 2003 to 2019, The Washington Post Company published a daily free commuter newspaper called the Express, which summarized events, sports and entertainment;  it still publishes the Spanish-language paper El Tiempo Latino.
Another popular local daily is The Washington Times, the city's second general interest broadsheet and also an influential paper in conservative political circles.  The alternative weekly Washington City Paper also has a substantial readership in the Washington area.  
Some community and specialty papers focus on neighborhood and cultural issues, including the weekly Washington Blade and Metro Weekly, which focus on LGBT issues; the Washington Informer and The Washington Afro American, which highlight topics of interest to the black community; and neighborhood newspapers published by The Current Newspapers. Congressional Quarterly, The Hill, Politico and Roll Call newspapers focus exclusively on issues related to Congress and the federal government. Other publications based in Washington include the National Geographic magazine and political publications such as The Washington Examiner, The New Republic and Washington Monthly. 
The Washington Metropolitan Area is the ninth-largest television media market in the nation, with two million homes, approximately 2% of the country's population.  Several media companies and cable television channels have their headquarters in the area, including C-SPAN; Black Entertainment Television (BET); Radio One; the National Geographic Channel; Smithsonian Networks; National Public Radio (NPR); Travel Channel (in Chevy Chase, Maryland); Discovery Communications (in Silver Spring, Maryland); and the Public Broadcasting Service (PBS) (in Arlington, Virginia). The headquarters of Voice of America, the U.S. government's international news service, is near the Capitol in Southwest Washington. 
Government and politics
Article One, Section Eight of the United States Constitution grants the United States Congress "exclusive jurisdiction" over the city. The District did not have an elected local government until the passage of the 1973 Home Rule Act. The Act devolved certain Congressional powers to an elected mayor, currently Muriel Bowser, and the thirteen-member Council of the District of Columbia. However, Congress retains the right to review and overturn laws created by the council and intervene in local affairs. 
Each of the city's eight wards elects a single member of the council and residents elect four at-large members to represent the District as a whole. The council chair is also elected at-large.  There are 37 Advisory Neighborhood Commissions (ANCs) elected by small neighborhood districts. ANCs can issue recommendations on all issues that affect residents; government agencies take their advice under careful consideration.  The Attorney General of the District of Columbia, currently Karl Racine, is elected to a four-year term. 
Washington, D.C., observes all federal holidays and also celebrates Emancipation Day on April 16, which commemorates the end of slavery in the District.  The flag of Washington, D.C., was adopted in 1938 and is a variation on George Washington's family coat of arms. 
Washington, D.C. is overwhelmingly Democratic, having voted for the Democratic candidate solidly since 1964. Each Republican candidate was voted down in favor of the Democratic candidate by a margin of at least 56 percentage points each time; the closest, albeit very large, margin between the two parties in a presidential election was in 1972, when Richard Nixon secured 21.6 percent of the vote to George McGovern's 78.1 percent. Since then, the Republican candidate has never received more than 20 percent of the vote.
Same-sex marriage has been legal in the District since 2010, and conversion therapy has been forbidden since 2015. Assisted suicide is also permitted in the district, with a bill legalizing the practice being introduced in 2015, signed by mayor Muriel Bowser in 2016 and going into effect in 2017, making Washington, D.C. the seventh jurisdiction in the United States to have legalized assisted suicide, along with Washington, Oregon, California, Colorado, Hawaii, Montana and Vermont.
Washington, D.C. has been a member state of the Unrepresented Nations and Peoples Organization (UNPO) since 2015.
The mayor and council set local taxes and a budget, which must be approved by Congress. The Government Accountability Office and other analysts have estimated that the city's high percentage of tax-exempt property and the Congressional prohibition of commuter taxes create a structural deficit in the District's local budget of anywhere between $470 million and over $1 billion per year. Congress typically provides additional grants for federal programs such as Medicaid and the operation of the local justice system; however, analysts claim that the payments do not fully resolve the imbalance.  
The city's local government, particularly during the mayoralty of Marion Barry, was criticized for mismanagement and waste.  During his administration in 1989, The Washington Monthly magazine claimed that the District had "the worst city government in America".  In 1995, at the start of Barry's fourth term, Congress created the District of Columbia Financial Control Board to oversee all municipal spending.  Mayor Anthony Williams won election in 1998 and oversaw a period of urban renewal and budget surpluses.
The District regained control over its finances in 2001 and the oversight board's operations were suspended. 
The District has a federally funded "Emergency Planning and Security Fund" to cover security related to visits by foreign leaders and diplomats, presidential inaugurations, protests, and terrorism concerns. During the Trump administration, the fund has run with a deficit. Trump's January 2017 inauguration cost the city $27 million; of that, $7 million was never repaid to the fund. Trump's 2019 Independence Day event, "A Salute to America", cost six times more than Independence Day events in past years. 
Voting rights debate
|1964||85.5% 169,796||14.5% 28,801|
|1968||81.8% 139,566||18.2% 31,012|
|1972||78.1% 127,627||21.6% 35,226|
|1976||81.6% 137,818||16.5% 27,873|
|1980||74.9% 130,231||13.4% 26,218|
|1984||85.4% 180,408||13.7% 29,009|
|1988||82.6% 159,407||14.3% 27,590|
|1992||84.6% 192,619||9.1% 20,698|
|1996||85.2% 158,220||9.3% 17,339|
|2000||85.2% 171,923||9.0% 18,073|
|2004||89.0% 202,970||9.3% 21,256|
|2008||92.5% 245,800||6.5% 17,367|
|2012||90.9% 267,070||7.3% 21,381|
|2016||90.9% 282,830||4.1% 12,723|
|1974||82.5% 79,065||3.7% 3,501|
|1978||70.2% 68,354||28.1% 27,366|
|1982||81.0% 95,007||14.1% 16,502|
|1986||61.4% 79,142||32.8% 42,354|
|1990||86.2% 140,011||11.5% 18,653|
|1994||56.0% 102,884||41.9% 76,902|
|1998||66.2% 92,504||30.2% 42,280|
|2002||60.6% 79,841||34.5% 45,407|
|2006||89.7% 98,740||6.1% 6,744|
The District is not a state and therefore has no voting representation in Congress. D.C. residents elect a non-voting delegate to the House of Representatives, currently Eleanor Holmes Norton (D- D.C. At-Large), who may sit on committees, participate in debate, and introduce legislation, but cannot vote on the House floor. The District has no official representation in the United States Senate. Neither chamber seats the District's elected "shadow" representative or senators. Unlike residents of U.S. territories such as Puerto Rico or Guam, which also have non-voting delegates, D.C. residents are subject to all federal taxes.  In the financial year 2012, D.C. residents and businesses paid $20.7 billion in federal taxes; more than the taxes collected from 19 states and the highest federal taxes per capita. 
A 2005 poll found that 78% of Americans did not know residents of the District of Columbia have less representation in Congress than residents of the fifty states.  Efforts to raise awareness about the issue have included campaigns by grassroots organizations and featuring the city's unofficial motto, " Taxation Without Representation", on D.C. vehicle license plates.  There is evidence of nationwide approval for D.C. voting rights; various polls indicate that 61 to 82% of Americans believe D.C. should have voting representation in Congress.  
Several approaches to resolving these concerns been suggested over the years:
- District of Columbia Statehood: The District of Columbia would become the 51st State in the Union.
- District of Columbia Retrocession to Maryland: As Arlington County in 1846 was retroceded to Virginia, proponents believe the rest of the District of Columbia with the exception of a small strip of land around the Capitol and the White House would be given back to Maryland allowing for DC residents to become Maryland residents as they were prior to the Residence Act of 1790.
- District of Columbia Voting Rights Amendment: this option would allow DC residents to vote in Maryland or Virginia for their congressional representatives, with the District of Columbia remaining an independent entity. This was in effect from 1790 to 1801, prior to the Organic Act of 1801.
Opponents of D.C. voting rights propose that the Founding Fathers never intended for District residents to have a vote in Congress since the Constitution makes clear that representation must come from the states. Those opposed to making D.C. a state claim such a move would destroy the notion of a separate national capital and that statehood would unfairly grant Senate representation to a single city. 
Washington, D.C., has fifteen official sister city agreements. Each of the listed cities is a national capital except for Sunderland, which includes the town of Washington, the ancestral home of George Washington's family.  Paris and Rome are each formally recognized as a partner city due to their special one sister city policy.  Listed in the order each agreement was first established, they are:
- Bangkok, Thailand (1962, renewed 2002 and 2012)
- Dakar, Senegal (1980, renewed 2006)
- Beijing, China (1984, renewed 2004 and 2012)
- Brussels, Belgium (1985, renewed 2002 and 2011)
- Athens, Greece (2000)
- Paris, France (2000 as a friendship and cooperation agreement, renewed 2005)  
- Pretoria, South Africa (2002, renewed 2008 and 2011)
- Seoul, South Korea (2006)
- Accra, Ghana (2006)
- Sunderland, United Kingdom (2006, renewed 2012) 
- Rome, Italy (2011, renewed 2013) 
- Ankara, Turkey (2011)
- Brasília, Brazil (2013)
- Addis Ababa, Ethiopia (2013) 
- San Salvador, El Salvador (2018)
District of Columbia Public Schools (DCPS) operates the city's 123 public schools.  The number of students in DCPS steadily decreased for 39 years until 2009. In the 2010–11 school year, 46,191 students were enrolled in the public school system.  DCPS has one of the highest-cost, yet lowest-performing school systems in the country, in terms of both infrastructure and student achievement.  Mayor Adrian Fenty's administration made sweeping changes to the system by closing schools, replacing teachers, firing principals, and using private education firms to aid curriculum development. 
The District of Columbia Public Charter School Board monitors the 52 public charter schools in the city.  Due to the perceived problems with the traditional public school system, enrollment in public charter schools has steadily increased.  As of 2010, D.C., charter schools had a total enrollment of about 32,000, a 9% increase from the prior year.  The District is also home to 92 private schools, which enrolled approximately 18,000 students in 2008.  The District of Columbia Public Library operates 25 neighborhood locations including the landmark Martin Luther King Jr. Memorial Library. 
Private universities include American University (AU), the Catholic University of America (CUA), Gallaudet University, George Washington University (GW), Georgetown University (GU), Howard University (HU), the Johns Hopkins University School of Advanced International Studies (SAIS), and Trinity Washington University. The Corcoran College of Art and Design, the oldest arts school in the capital, was absorbed into the George Washington University in 2014, now serving as its college of arts.
The University of the District of Columbia (UDC) is a public land-grant university providing undergraduate and graduate education. D.C. residents may also be eligible for a grant of up to $10,000 per year to offset the cost of tuition at any public university in the country. 
The District is known for its medical research institutions such as Washington Hospital Center and the Children's National Medical Center, as well as the National Institutes of Health in Bethesda, Maryland. In addition, the city is home to three medical schools and associated teaching hospitals at George Washington, Georgetown, and Howard universities. 
There are 1,500 miles (2,400 km) of streets, parkways, and avenues in the District.  Due to the freeway revolts of the 1960s, much of the proposed interstate highway system through the middle of Washington was never built. Interstate 95 (I-95), the nation's major east coast highway, therefore bends around the District to form the eastern portion of the Capital Beltway. A portion of the proposed highway funding was directed to the region's public transportation infrastructure instead.  The interstate highways that continue into Washington, including I-66 and I-395, both terminate shortly after entering the city. 
The Washington Metropolitan Area Transit Authority (WMATA) operates the Washington Metro, the city's rapid transit system, as well as Metrobus. Both systems serve the District and its suburbs. Metro opened on March 27, 1976 and, as of 2014 [update], consists of 91 stations and 117 miles (188 km) of track.  With an average of about one million trips each weekday, Metro is the second-busiest rapid transit system in the country. Metrobus serves more than 400,000 riders each weekday and is the nation's fifth-largest bus system.  The city also operates its own DC Circulator bus system, which connects commercial areas within central Washington. 
Union Station is the city's main train station and services approximately 70,000 people each day. It is Amtrak's second-busiest station with 4.6 million passengers annually and is the southern terminus for the Northeast Corridor and Acela Express routes. Maryland's MARC and Virginia's VRE commuter trains and the Metrorail Red Line also provide service into Union Station.  Following renovations in 2011, Union Station became Washington's primary intercity bus transit center.  Three major airports serve the District. Ronald Reagan Washington National Airport is across the Potomac River from downtown Washington in Arlington, Virginia and primarily handles domestic flights. Major international flights arrive and depart from Washington Dulles International Airport, 26.3 miles (42.3 km) west of the District in Fairfax and Loudoun counties in Virginia. Baltimore-Washington International Thurgood Marshall Airport is 31.7 miles (51.0 km) northeast of the District in Anne Arundel County, Maryland.
According to a 2010 study, Washington-area commuters spent 70 hours a year in traffic delays, which tied with Chicago for having the nation's worst road congestion.  However, 37% of Washington-area commuters take public transportation to work, the second-highest rate in the country.  An additional 12% of D.C. commuters walked to work, 6% carpooled, and 3% traveled by bicycle in 2010.  A 2011 study by Walk Score found that Washington was the seventh-most walkable city in the country with 80% of residents living in neighborhoods that are not car dependent.  In 2013, the Washington-Arlington-Alexandria metropolitan statistical area (MSA) had the eighth lowest percentage of workers who commuted by private automobile (75.7 percent), with 8 percent of area workers traveling via rail transit. 
An expected 32% increase in transit usage within the District by 2030 has spurred the construction of a new DC Streetcar system to interconnect the city's neighborhoods.  Construction is also finishing on an additional Metro line that will connect Washington to Dulles airport.  The District is part of the regional Capital Bikeshare program. Started in 2010, it is currently one of the largest bicycle sharing systems in the country with more than 4,351 bicycles and more than 395 stations,  all provided by PBSC Urban Solutions. By 2012, the city's network of marked bicycle lanes covered 56 miles (90 km) of streets. 
The District of Columbia Water and Sewer Authority (i.e. WASA or D.C. Water) is an independent authority of the D.C. government that provides drinking water and wastewater collection in Washington. WASA purchases water from the historic Washington Aqueduct, which is operated by the Army Corps of Engineers. The water, sourced from the Potomac River, is treated and stored in the city's Dalecarlia, Georgetown, and McMillan reservoirs. The aqueduct provides drinking water for a total of 1.1 million people in the District and Virginia, including Arlington, Falls Church, and a portion of Fairfax County.  The authority also provides sewage treatment services for an additional 1.6 million people in four surrounding Maryland and Virginia counties. 
Pepco is the city's electric utility and services 793,000 customers in the District and suburban Maryland.  An 1889 law prohibits overhead wires within much of the historic City of Washington. As a result, all power lines and telecommunication cables are located underground in downtown Washington, and traffic signals are placed at the edge of the street.  A plan announced in 2013 would bury an additional 60 miles (97 km) of primary power lines throughout the District. 
Washington Gas is the city's natural gas utility and serves more than a million customers in the District and its suburbs. Incorporated by Congress in 1848, the company installed the city's first gas lights in the Capitol, the White House, and along Pennsylvania Avenue. 
- By 1790, the Southern states had largely repaid their overseas debts from the Revolutionary War. The Northern states had not, and wanted the federal government to take over their outstanding liabilities. Southern Congressmen agreed to the plan in return for establishing the new national capital at their preferred site on the Potomac River. 
- The Residence Act allowed the President to select a location within Maryland as far east as the Anacostia River. However, Washington shifted the federal territory's borders to the southeast in order to include the city of Alexandria at the District's southern tip. In 1791, Congress amended the Residence Act to approve the new site, including territory ceded by Virginia. 
- Mean monthly maxima and minima (i.e. the expected highest and lowest temperature readings at any point during the year or given month) calculated based on data at said location from 1981 to 2010.
- Official records for Washington, D.C. were kept at 24th and M Streets NW from January 1871 to June 1945, and at Reagan National since July 1945. 
- Until 1890, the Census Bureau counted the City of Washington, Georgetown, and unincorporated portions of Washington County as three separate areas. The data provided in this article from before 1890 are calculated as if the District of Columbia were a single municipality as it is today. Population data for each city prior to 1890 are available. 
- The territories of the United States have the highest poverty rates in the United States. 
- These figures count adherents, meaning all full members, their children, and others who regularly attend services. In all of the District, 55% of the population is adherent to any particular religion.
- Independents David Catania and Carol Schwartz, both former Republicans, garnered 61,388 and 12,327 votes, or 34.6% and 7.0%, respectively.
- Imhoff, Gary (October 1999). "Our Official Songs". DC Watch. Retrieved February 7, 2012.
- "U.S. Census Bureau QuickFacts: District of Columbia". www.census.gov.
- "Demonyms for people from the USA". www.geography-site.co.uk. Retrieved April 12, 2017.
- "Demonym". addis.com. Archived from the original on April 13, 2017. Retrieved April 12, 2017.
- Jamie R. Liu (July 14, 2011). "Rickey Named Official D.C. Cocktail". DCist. Archived from the original on October 14, 2011. Retrieved July 14, 2011.
- "Introduction: Where Oh Where Should the Capital Be?". WHHA.
- "Washington, D.C. History F.A.Q." The Historical Society of Washington, D.C. May 27, 2014. Retrieved March 7, 2018.
Broder, David S. (February 18, 1990).
"Nation's Capital in Eclipse as Pride and Power Slip Away".
The Washington Post. Retrieved October 18, 2010.
In the days of the Truman Doctrine, the Marshall Plan and the creation of NATO, [Clark Clifford] said, we saved the world, and Washington became the capital of the world.
- "The 10 most-visited cities in the US this year". Insider. Retrieved March 6, 2018.
- Cooper, Rebecca (May 9, 2017). "D.C. breaks another domestic tourism record". www.bizjournals.com. Washington Business Journal.
- "Population and Housing Unit Estimates". Retrieved May 21, 2020.
- "Washington-Arlington-Alexandria, DC-VA-MD-WV". U.S. Census Bureau. U.S. Department of Commerce. Retrieved April 12, 2017.
- "Washington, D.C. metrostatistical2017". U.S. Census Bureau. U.S. Department of Commerce. Retrieved February 4, 2019.
- "States, Counties, and Statistically Equivalent Entities (Chapter 4)" (PDF). Census.gov. Retrieved July 3, 2019.
- Humphrey, Robert Lee; Chambers, Mary Elizabeth (1977). Ancient Washington: American Indian Cultures of the Potomac Valley. George Washington University. ISBN 9781888028041. Retrieved March 6, 2018.
- Madison, James. "The Federalist No. 43". The Independent Journal. Library of Congress. Retrieved September 5, 2011.
- Crew, Harvey W.; Webb, William Bensing; Wooldridge, John (1892). "IV. Washington Becomes The Capital". Centennial History of the City of Washington, D.C. Dayton, OH: United Brethren Publishing House. p. 66.
- "Constitution of the United States". National Archives and Records Administration. Retrieved July 22, 2008.
- Crew, Harvey W.; Webb, William Bensing; Wooldridge, John (1892). Centennial History of the City of Washington, D.C. Dayton, OH: United Brethren Publishing House. p. 124.
- Crew, Harvey W.; Webb, William Bensing; Wooldridge, John (1892). Centennial History of the City of Washington, D.C. Dayton, OH: United Brethren Publishing House. pp. 89–92.
- "Georgetown Historic District". National Park Service. Retrieved July 5, 2008.
- "Alexandria's History". Alexandria Historical Society. Archived from the original on April 4, 2009. Retrieved April 4, 2009.
- Bordewich, Fergus M. (2008). Washington: the making of the American capital. HarperCollins. pp. 76–80. ISBN 978-0-06-084238-3.
- "Boundary Stones of the District of Columbia". BoundaryStones.org. Retrieved May 27, 2008.
- Crew, Harvey W.; Webb, William Bensing; Wooldridge, John (1892). "IV. Permanent Capital Site Selected". Centennial History of the City of Washington, D.C. Dayton, OH: United Brethren Publishing House. p. 101. Retrieved June 1, 2011.
- "Get to Know D.C." Historical Society of Washington, D.C. Archived from the original on September 18, 2010. Retrieved July 11, 2011.
- "The Senate Moves to Washington". United States Senate. February 14, 2006. Retrieved July 11, 2008.
- Tom (July 24, 2013). "Why Is Washington, D.C. Called the District of Columbia?". Ghosts of DC. Retrieved February 20, 2019.
- Crew, Harvey W.; Webb, William Bensing; Wooldridge, John (1892). "IV. Permanent Capital Site Selected". Centennial History of the City of Washington, D.C. Dayton, OH: United Brethren Publishing House. p. 103.
- "Statement on the subject of The District of Columbia Fair and Equal Voting Rights Act" (PDF). American Bar Association. September 14, 2006. Retrieved August 10, 2011.
- "Saving History: Dolley Madison, the White House, and the War of 1812". White House Historical Association. Retrieved February 21, 2010.
- "A Brief Construction History of the Capitol". Architect of the Capitol. Retrieved December 2, 2012.
- Richards, Mark David (Spring–Summer 2004). "The Debates over the Retrocession of the District of Columbia, 1801–2004" (PDF). Washington History: 54–82. Archived from the original (PDF) on January 18, 2009. Retrieved January 16, 2009.
- Greeley, Horace (1864). The American Conflict: A History of the Great Rebellion in the United States. Chicago: G. & C.W. Sherwood. pp. 142–144.
- "Compromise of 1850". Library of Congress. September 21, 2007. Retrieved July 24, 2008.
- Dodd, Walter Fairleigh (1909). The government of the District of Columbia. Washington, D.C.: John Byrne & Co. pp. 40–45.
- "Ending Slavery in the District of Columbia". D.C. Office of the Secretary. Retrieved May 12, 2012.
- "Historical Census Statistics on Population Totals By Race, 1790 to 1990" (PDF). United States Census Bureau. September 13, 2002. Archived from the original (PDF) on August 4, 2011. Retrieved August 13, 2011.
- Bordewich, Fergus M. (2008). Washington: the making of the American capital. HarperCollins. p. 272. ISBN 978-0-06-084238-3.
- "An Act to provide a Government for the District of Columbia". Statutes at Large, 41st Congress, 3rd Session. Library of Congress. Retrieved July 10, 2011.
- Wilcox, Delos Franklin (1910). Great cities in America: their problems and their government. The Macmillan Company. pp. 27–30.
- Kathryn Schneider Smith, ed. (2010). Washington at Home: An Illustrated History of Neighborhoods in the Nation's Capital (2 ed.). Johns Hopkins University Press. pp. 1–11. ISBN 978-0-8018-9353-7.
- Tindall, William (1907). Origin and government of the District of Columbia. Washington, D.C.: U.S. Government Printing Office. pp. 26–28.
- Ramroth, William (2007). "The City Beautiful Movement". Planning for Disaster. Kaplan. p. 91. ISBN 978-1-4195-9373-4.
- Gelernter, Mark (2001). History of American Architecture. Manchester University Press. p. 248. ISBN 978-0-7190-4727-5.
- Home Rule or House Rule? Congress and the Erosion of Local Governance in the District of Columbia by Michael K. Fauntroy, University Press of America, 2003 at Google Books, page 94
- Williams, Paul Kelsey (2004). Washington, D.C.: the World War II years. Arcadia Publishing. ISBN 978-0-7385-1636-3.
- "Twenty-third Amendment". CRS Annotated Constitution. Legal Information Institute (Cornell University Law School). Retrieved August 28, 2012.
- Schwartzman, Paul; Robert E. Pierre (April 6, 2008). "From Ruins To Rebirth". The Washington Post. Retrieved June 6, 2008.
- "District of Columbia Home Rule Act". Government of the District of Columbia. February 1999. Retrieved May 27, 2008.
- Mathews, Jay (October 11, 1999). "City's 1st Mayoral Race, as Innocent as Young Love". The Washington Post. p. A1.
- "District of Columbia: 2010" (PDF). United States Census Bureau. June 2012. Retrieved December 22, 2015.
- "Facts & FAQs". Interstate Commission on the Potomac River Basin. Archived from the original on August 13, 2012. Retrieved March 31, 2012.
- Grant III, Ulysses Simpson (1950). "Planning the Nation's Capital". Records of the Columbia Historical Society. 50: 43–58.
- Heine, Cornelius W. (1953). "The Washington City Canal". Records of the Columbia Historical Society. 53: 1–27. JSTOR 40067664.
- "C&O Canal National Historic Park: History & Culture". National Park Service. Retrieved July 3, 2008.
- Dvorak, Petula (April 18, 2008). "D.C.'s Puny Peak Enough to Pump Up 'Highpointers'". Washington Post. pp. B01. Retrieved February 25, 2009.
- Winegar, Deane (2003). Highroad Guide to the Chesapeake Bay. John F. Blair. p. 5. ISBN 978-0-89587-279-1.
- "Science in Your State: District of Columbia". United States Geological Survey. July 30, 2007. Retrieved July 7, 2008.
- Reilly, Mollie (May 12, 2012). "Washington's Myths, Legends, and Tall Tales—Some of Which Are True". Washingtonian. Retrieved August 29, 2011.
- Kelly, John (April 1, 2012). "Washington Built on a Swamp? Think Again". The Washington Post.
- "2011 City Park Facts" (PDF). The Trust for Public Land. 2011. Retrieved December 9, 2011.
- "ParkScore". www.parkscore.tpl.org. Retrieved May 23, 2018.
- "Comparison of Federally Owned Land with Total Acreage of States" (PDF). Bureau of Land Management. 1999. Archived from the original (PDF) on October 16, 2011. Retrieved July 19, 2011.
- "Rock Creek Park". Geology Fieldnotes. National Park Service. Archived from the original on February 4, 2013. Retrieved February 3, 2013.
- "District of Columbia". National Park Service. Retrieved October 16, 2011.
- "FY12 Performance Plan" (PDF). D.C. Department of Parks and Recreation. Retrieved February 3, 2013.
- "U.S. National Arboretum History and Mission". United States National Arboretum. October 16, 2007. Archived from the original on August 5, 2011. Retrieved July 7, 2008.
- Kottek, Markus; Grieser, Jürgen; Beck, Christoph; Rudolf, Bruno; Rubel, Franz (November 6, 2008). "World Map of the Köppen-Geiger climate classification updated". Meteorologische Zeitschrift. 15 (3): 259. Bibcode: 2006MetZe..15..259K. doi: 10.1127/0941-2948/2006/0130. Archived from the original on September 6, 2010. Retrieved December 3, 2009.
- Peterson, Adam (September 22, 2016), English: Trewartha climate types for the contiguous United States, retrieved March 8, 2019
- "Hardiness Zones". Arbor Day Foundation. 2006. Retrieved November 4, 2008.
- "NowData - NOAA Online Weather Data". National Oceanic and Atmospheric Administration. Retrieved October 3, 2019.
- "Average Conditions: Washington DC, USA". BBC Weather. Retrieved August 30, 2010.
- Iovino, Jim. "Severe Storm Warnings, Tornado Watches Expire". NBCWashington.com. Retrieved August 30, 2010.
- Watson, Barbara McNaught (November 17, 1999). "Washington Area Winters". National Weather Service. Archived from the original on December 31, 2010. Retrieved September 17, 2010.
- Ambrose, Kevin; Junker, Wes (January 23, 2016). "Where Snowzilla fits into D.C.'s top 10 snowstorms". Washington Post.
- Heidorn, Keith C. (January 1, 2012). "The Washington and Jefferson Snowstorm of 1772". The Weather Doctor. Retrieved January 25, 2016.
- Schwartz, Rick (2007). Hurricanes and the Middle Atlantic States. Blue Diamond Books. p. 9. ISBN 978-0-9786280-0-0.
- Vogel, Steve (June 28, 2006). "Bulk of Flooding Expected in Old Town, Washington Harbour". The Washington Post. p. B02. Retrieved July 11, 2008.
- "WMO Climate Normals for WASHINGTON DC/NATIONAL ARPT VA 1961–1990". National Oceanic and Atmospheric Administration. Retrieved September 7, 2016.
- United States Environmental Protection Agency. (2016). What Climate Change Means for the District of Columbia. (Report No. 123).
- Samenow, Jason (June 29, 2012). "Washington, D.C. shatters all-time June record high, sizzles to 104". The Washington Post.
- Grieser, Justin; Livingston, Ian (November 8, 2017). " The first freeze is coming Saturday and, for most of the D.C. area, it's historically late". The Washington Post.
- Livingston, Ian; Grieser, Justin (April 3, 2018). " When will the last freeze happen around the D.C. region, and when is it safe to plant?" The Washington Post.
- "Threaded Station Extremes". threadex.rcc-acis.org.
- "Station Name: VA WASHINGTON REAGAN AP". National Oceanic and Atmospheric Administration. Retrieved February 27, 2018.
- Rogers, Matt (April 1, 2015).
"April outlook: Winter be gone! First half of month looks warmer than average".
The Washington Post. Retrieved August 21, 2018.
For reference, here are the 30-year climatology benchmarks for Reagan National Airport for April, along with our projections for the coming month:...Average snowfall: Trace; Forecast: 0 to trace
- d.o.o, Yu Media Group. "Washington, DC - Detailed climate information and monthly weather forecast". Weather Atlas. Retrieved June 29, 2019.
- Coleman, Christopher Bush (1920). Indiana Magazine of History. Indiana Historical Society. p. 109.
- "The L'Enfant and McMillan Plans". National Park Service. Retrieved May 27, 2008.
- Minta, Anna (2009). Klaus Benesch; Jeffrey L. Meilke; David E. Nye; Miles Orvell (eds.). Planning a National Pantheon: Monuments in Washington, D.C. and the Creation of Symbolic Space. Public Space and the Ideology of Place in American Culture. Amsterdam—New York: Rodopi B.V. p. 22. ISBN 978-90-420-2574-5. OCLC 644525117.
- "Map 1: The L'Enfant Plan for Washington". National Park Service. Retrieved October 27, 2009.
- Crew, Harvey W.; Webb, William Bensing; Wooldridge, John (1892). Centennial History of the City of Washington, D.C. Dayton, OH: United Brethren Publishing House. pp. 101–103.
- Schwartzman, Paul (May 2, 2007). "High-Level Debate on Future of D.C." The Washington Post. Retrieved July 1, 2012.
- "Layout of Washington DC". United States Senate. September 30, 2005. Retrieved July 14, 2008.
- Laws relating to the permanent system of highways outside of the cities of Washington and Georgetown. Washington, D.C.: Government Printing Office. 1908. p. 3.
- Birnbaum, Jeffrey H. (June 22, 2005). "The Road to Riches Is Called K Street". The Washington Post. p. A01. Retrieved June 17, 2008.
- Van Dyne, Larry (February 1, 2008). "Foreign Affairs: DC's Best Embassies". Washingtonian Magazine. Retrieved June 17, 2012.
- "America's Favorite Architecture". American Institute of Architects and Harris Interactive. 2007. Archived from the original on May 10, 2011. Retrieved July 3, 2008.
- "Washington, D.C., List of Sites". National Park Service. Retrieved December 12, 2010.
- Scott, Pamela (2005). "Residential Architecture of Washington, D.C., and Its Suburbs". Library of Congress. Retrieved June 5, 2008.
- "Old Stone House". National Park Service. Retrieved August 13, 2011.
- "Our Building". Ronald Reagan Building and International Trade Center. Archived from the original on January 15, 2013. Retrieved January 6, 2013.
- "Resident Population Data". United States Census Bureau. 2010. Archived from the original on February 17, 2013. Retrieved January 6, 2013.
- Gibson, Campbell (June 1998). "Population of the 100 Largest Cities and Other Urban Places in the United States: 1790 to 1990". United States Census Bureau. Retrieved July 29, 2008.
- "Demographic Characteristics of the District and Metro Area" (PDF). DC Office of Planning/State Data Center.
- "District of Columbia—Race and Hispanic Origin for Selected Cities and Other Places: Earliest Census to 1990". U.S. Census Bureau. Archived from the original on August 12, 2012. Retrieved April 21, 2012.
- From 15% sample
- Morello, Carol; Keating, Dan (December 22, 2011). "D.C. population soars past 600,000 for first time in years". The Washington Post. Retrieved August 26, 2011.
- "Population Change for Places With Populations of 50,000 or More in the United States and Puerto Rico: 2000 to 2010". United States Census Bureau. September 27, 2011. Retrieved December 21, 2011.
- Austermuhle, Martin (May 31, 2013). "D.C.'s Population Grows 79 Percent Every Workday, Outpacing Other Cities". WAMU. Retrieved June 1, 2013.
- "QuickFacts: District of Columbia". U.S. Census Bureau. July 1, 2017. Retrieved October 11, 2018.
- "Annual Estimates of the Resident Population: April 1, 2010 to July 1, 2016". United States Census Bureau, Population Division. March 2017. Archived from the original on February 13, 2020. Retrieved March 6, 2018.
- "Annual Estimates of the Resident Population: April 1, 2010 to July 1, 2016—United States—Combined Statistical Area; and for Puerto Rico". United States Census Bureau, Population Division. March 2017. Archived from the original on February 13, 2020. Retrieved March 6, 2018.
- Kolchin, Peter (1994). American Slavery: 1619–1877. New York: Hill and Wang. p. 81.
- Morello, Carol; Keating, Dan (March 24, 2011). "Number of black D.C. residents plummets as majority status slips away". The Washington Post. Retrieved March 25, 2011.
- "'It's primarily racial': Study finds DC has the most intense gentrification in the country". WTOP. April 18, 2019. Retrieved June 12, 2020.
- "Age and Sex Composition: 2010" (PDF). United States Census Bureau. May 2011. p. 7. Retrieved August 17, 2011.
- Singer, Audrey; et al. (2001). "The World in a Zip Code: Greater Washington, D.C. as a New Region of Immigration". The Brookings Institution. Retrieved May 12, 2012.
- Gates, Gary J.; Abigail M. Cooke (September 2011). "District of Columbia Census Snapshot: 2010" (PDF). The Williams Institute. Retrieved November 12, 2011.
- Alexander, Keith L.; Anne E. Marimow (March 4, 2010). "D.C. begins licensing same-sex marriages". The Washington Post. Retrieved March 4, 2010.
- "Study Finds One-third in D.C. Illiterate". Associated Press. March 19, 2007. Archived from the original on March 22, 2007. Retrieved August 13, 2011.
- Ryan, Camille (August 2013). "Language Use in the United States: 2011" (PDF). American Community Survey. U.S. Census Bureau. Archived from the original (PDF) on February 5, 2016. Retrieved August 11, 2013.
- "Per Capita Income in the Past 12 Months (in 2017 Inflation-Adjusted Dollars) 2013-2017 American Community Survey 5-Year estimates. (Geography set to "District of Columbia")". American FactFinder. Archived from the original on February 14, 2020. Retrieved July 3, 2019.
- "Personal Income Per Capita in Current and Constant (2000) Dollars by State: 2000 to 2006" (PDF). United States Census Bureau. April 2007. Archived from the original (PDF) on December 28, 2008. Retrieved December 27, 2008.
- "Individuals and Families Below Poverty Level—Number and Rate by State: 2000 and 2005" (PDF). United States Census Bureau. 2005. Archived from the original (PDF) on December 28, 2008. Retrieved December 27, 2008.
- "Poverty Determination In U.S. Insular Areas" (PDF). GAO. Retrieved July 3, 2019.
- "Historical Poverty Tables: People and Families—1959 to 2018". 2018. Retrieved October 8, 2019.
- "County Membership Report: District of Columbia: Religious Traditions, 2010". Association of Religion Data Archives. Archived from the original on October 28, 2014.
- Reed, Jenny (April 21, 2010). "National Health Care Reform is a Win for DC". DC Fiscal Policy Institute. Archived from the original on October 2, 2011. Retrieved August 17, 2011.
- Vargas, Jose Antonio; Darryl Fears (March 15, 2009). "HIV/AIDS Rate in D.C. Hits 3%". The Washington Post. pp. A01. Retrieved March 21, 2009.
- "Religious composition of adults in the District of Columbia". Pew Research Center's Religion & Public Life Project. May 11, 2015.
- Cahill, Meagan; John K. Roman (November 2010). "Small Number of Blocks Account for Lots of Crime in D.C." (PDF). District of Columbia Crime Policy Institute. Archived from the original (PDF) on October 16, 2011. Retrieved June 25, 2011.
- Pierre, Robert (July 2, 2008). "Ex-Offenders Protest Dearth of Jobs, Services". The Washington Post. Retrieved May 2, 2011.
- Mollenbeck, Andrew (January 3, 2013). "District celebrates historically low homicide rate". WTOP. Retrieved January 14, 2013.
- "Crime rate in Washington, District of Columbia (DC)". City-data.com.
- Urbina, Ian (July 13, 2006). "Washington Officials Try to Ease Crime Fear". The New York Times. Retrieved June 10, 2008.
- Klein, Allison; Zapotosky, Matt (December 31, 2011). "As homicides fall in D.C., rise in Prince George's, numbers meet in the middle". The Washington Post. Retrieved January 2, 2012.
- "District Crime Data". Mpdc.dc.gov.
- Klein, Allison; Dan Keating (October 13, 2006). "Liveliest D.C. Neighborhoods Also Jumping With Robberies". The Washington Post. Retrieved June 26, 2011.
- "District of Columbia Crime Rates 1960–2010". Disaster Center. Retrieved September 22, 2012.
- Barnes, Robert (June 26, 2008). "Supreme Court Strikes Down D.C. Ban on Handguns". The Washington Post. Retrieved June 27, 2008.
- Nakamura, David (June 26, 2008). "D.C. Attorney General: All Guns Must Be Registered". The Washington Post. Archived from the original on October 11, 2008. Retrieved June 26, 2008.
- "U.S. Park Police Authority and Jurisdiction". National Park Service. August 13, 2011. Retrieved August 13, 2011.
- Florida, Richard (June 2, 2011). "What Housing Crisis?". The New York Times. Retrieved November 15, 2011.
- Gross Domestic Product by State, U.S. Bureau of Economic Analysis, November 14, 2018
- Analysis, US Department of Commerce, BEA, Bureau of Economic. "Bureau of Economic Analysis". www.bea.gov. Retrieved January 11, 2016.
- Bureau of Economic Analysis. "Per capita real GDP by state (chained 2009 dollars)". www.bea.gov. U.S. Department of Commerce. Retrieved August 29, 2017.
- "Metropolitan Area Employment and Unemployment (Monthly) News Release". United States Bureau of Labor Statistics. July 8, 2011. Retrieved August 9, 2011.
- "Regional and State Employment and Unemployment (Monthly) News Release". United States Bureau of Labor Statistics. June 17, 2011. Retrieved August 9, 2011.
- " District of Columbia Wage and Salary Employment by Industry and Place of Work 2017". District of Columbia Department of Employment Services, Office of Labor Market Research and Information. 2017.
- "Wage and Salary Employment by Industry and Place of Work" (PDF). District of Columbia Department of Employment Services. 2012. Retrieved April 19, 2012.
- Gopal, Prashant (October 14, 2008). "Some Cities Will Be Safer in a Recession". BusinessWeek. Retrieved September 9, 2012.
- "Amazon's Grand Search For 2nd Headquarters Ends With Split: NYC And D.C. Suburb". NPR.org. Retrieved September 1, 2019.
- Connolly, Matt (May 7, 2013). "D.C. sets tourism record with 19m visitors in 2012". The Washington Examiner. Archived from the original on November 3, 2013. Retrieved May 8, 2013.
- "Top 200 Chief Executive Officers of the Major Employers in the District of Columbia 2009" (PDF). D.C. Department of Employment Services. 2010. Retrieved September 6, 2012.
- "Fortune 500 2011: States: District Of Columbia Companies". Fortune Magazine. CNNMoney.com. May 23, 2011. Retrieved November 12, 2011.
- "The Global Financial Centres Index 21" (PDF). China Development Institute. March 2017. Archived from the original (PDF) on September 18, 2018. Retrieved September 4, 2018.
- "National Mall & Memorial Parks: History & Culture". National Park Service. September 28, 2006. Retrieved February 18, 2012.
- "History of the Cherry Trees". National Park Service. Retrieved August 19, 2011.
- "Rotunda for the Charters of Freedom". The National Archives. Retrieved June 28, 2008.
- "General Information". Library of Congress. February 1, 2011. Retrieved July 9, 2011.
- "The Court Building". Supreme Court of the United States. Retrieved August 19, 2011.
- "Top 10 Museums and Galleries". National Geographic. September 20, 2012.
- "About the Smithsonian". Smithsonian Institution. Retrieved May 27, 2008.
- "Visitor Statistics". Smithsonian Institution. Retrieved February 20, 2014.
- "Museum and Program Fact Sheets". Smithsonian Institution. Retrieved August 13, 2011.
- Goodheart, Adam (2006). "Back to the Future". Smithsonian Magazine. Retrieved September 9, 2012.
- "About the National Gallery of Art". National Gallery of Art. Retrieved April 28, 2013.
- "About the National Building Museum". National Building Museum. Archived from the original on November 4, 2010. Retrieved November 6, 2010.
- "About The Phillips Collection". The Phillips Collection. Retrieved December 2, 2012.
- "Frequently Asked Questions". U.S. Holocaust Memorial Museum. January 14, 2008. Retrieved May 27, 2008.
- "About the Kennedy Center Honors". The Kennedy Center. Archived from the original on May 16, 2008. Retrieved June 29, 2008.
- Rothstein, Edward (February 6, 2009). "Where a Comedy Turned to Tragedy". The New York Times. Retrieved April 2, 2011.
- "Who We Are". United States Marine Band. Archived from the original on October 19, 2012. Retrieved July 23, 2011.
- Davison, Marjorie Risk (1969). "History of Music in the District of Columbia". Records of the Columbia Historical Society. 66–68: 183. Retrieved August 9, 2011.
- "History". United States Navy Band. Archived from the original on July 16, 2011. Retrieved July 23, 2011.
- Wilmeth, Don B.; C.W.E. Bigsby (2000). The Cambridge history of American theatre. Cambridge University Press. p. 232. ISBN 978-0-521-66959-7.
- Kravitz, Derek (September 26, 2010). "The emerging Southwest: Transformation underway". The Washington Post. Retrieved April 2, 2001.
- "Gala Theatre History". GALA Hispanic Theatre. Archived from the original on August 30, 2009. Retrieved April 2, 2001.
- Levin, Dan (September 10, 2006). "Lights Return to 'Black Broadway' in Northwest Washington, D.C." The New York Times. Archived from the original on June 10, 2011. Retrieved June 20, 2008.
- Wartofsky, Alona (June 3, 2001). "What Go-Goes Around ...". The Washington Post. p. G01.
- Constantinou, Costas M. (2008). Cultures and politics of global communication. Cambridge University Press. p. 203. ISBN 978-0-521-72711-2.
- "Black Cat: A changing club with a changing scene in a changing city". The Georgetown Voice. September 9, 2001. Archived from the original on May 13, 2011. Retrieved June 10, 2008.
- "History by Decades". Washington Redskins. Archived from the original on March 22, 2011. Retrieved May 29, 2011.
- "D.C. United History & Tradition". D.C. United. Retrieved June 13, 2010.
- "NBA Finals: All-Time Champions". National Basketball Association. 2008. Retrieved June 29, 2008.
- Khurshudyan, Isabelle; Stubbs, Roman; Dougherty, Jesse; Allen, Scott; Greenberg, Neil; Steinberg, Dan (June 8, 2018). "Capitals win Stanley Cup, Washington's first major sports championship since 1992". Washington Post. ISSN 0190-8286. Retrieved June 12, 2018.
- "MCM History". Marine Corps Marathon. Archived from the original on January 19, 2015. Retrieved May 18, 2011.
- "Emergence of the Bowl" (PDF). D.C. Bowl Committee. Archived from the original (PDF) on July 20, 2011. Retrieved May 18, 2011.
- "History of the Post". 2011. Retrieved May 29, 2011.
- "The Watergate Story Timeline". The Washington Post. Retrieved December 2, 2012.
- Edmonds, Rick; Emily Guskin; Tom Rosenstiel; Amy Mitchell. "Newspapers: By the Numbers". The State of the News Media 2012. Pew Research Center. Archived from the original on September 7, 2012. Retrieved September 9, 2012.
- Farhi, Paul (September 11, 2019). "Express, commuter newspaper published by The Washington Post, shuts down after 16 years". The Washington Post. Retrieved April 7, 2020.
- "Bush Sr. To Celebrate Rev. Sun Myung Moon—Again".
- "Times circulation climbs to buck trend". The Washington Times. May 18, 2005. Retrieved September 2, 2008.
- "Washington City Paper". Association of Alternative Newsweeklies. Retrieved August 12, 2011.
- "District of Columbia, 2010–2011". Chronicling America: Historic American Newspapers. Library of Congress. Retrieved August 17, 2011.
- "US TV Households Up 1.5%—Asian, Hispanic Households Triple That". Nielsen Media Research. September 27, 2008. Retrieved October 10, 2009.
- "About VOA". Voice of America. Retrieved December 2, 2012.
- "DC Home Rule". Council of the District of Columbia. Archived from the original on November 17, 2011. Retrieved December 3, 2011.
- "Current Elected Officials in DC". D.C. Board of Elections and Ethics. Retrieved January 11, 2012.
- "About ANC". Government of the District of Columbia. Retrieved September 22, 2012.
- "§ 1–204.35. Election of the Attorney General". Code of the District of Columbia (Unofficial). Open Law DC. Retrieved January 2, 2015.
- Glaser, Jason (2003). Washington, D.C.. Capstone. p. 55. ISBN 978-0-7368-2204-6.
- "Buildling the Best Capital City in the World" (PDF). DC Appleseed. Archived from the original (PDF) on May 11, 2011. Retrieved February 5, 2011.
- "District of Columbia Structural Imbalance and Management Issues" (PDF). Government Accountability Office. May 2003. Retrieved February 5, 2011.
- Powell, Michael (July 20, 2007). "Poor Management, Federal Rule, Undermine Services". The Washington Post. p. A01. Retrieved June 10, 2008.
- DeParle, Jason (January 1, 1989). "The worst city government in America". The Washington Monthly. Retrieved June 6, 2009.
- Janofsky, Michael (April 8, 1995). "Congress creates board to oversee Washington, D.C." The New York Times. Retrieved May 27, 2008.
- DeBonis, Mike (January 30, 2011). "After 10 years, D.C. control board is gone but not forgotten". The Washington Post. Retrieved July 11, 2011.
- Jamison, Peter (July 10, 2019). "Trump's July Fourth event and weekend protests bankrupted D.C. security fund, mayor says". Washington Post. Retrieved July 10, 2019.
- Leip, David. "General Election Results—District of Columbia". United States Election Atlas. Retrieved November 18, 2016.
- "Individuals Living or Working in U.S. Possessions". Internal Revenue Service. Archived from the original on December 2, 2012. Retrieved December 2, 2012.
- "Internal Revenue Gross Collections, by Type of Tax and State, Fiscal Year 2012" (XLS). Internal Revenue Service. Retrieved September 5, 2013.
- "Poll Shows Nationwide Support for DC Voting Rights" (PDF). DC Vote Voice. 2005. Archived from the original (PDF) on June 24, 2008. Retrieved May 29, 2008.
- "'Taxation without Representation' Tags". District of Columbia Department of Motor Vehicles. Archived from the original on January 15, 2013. Retrieved December 2, 2012.
- "Washington Post Poll: D.C. Voting Rights". The Washington Post. April 23, 2007. Retrieved June 10, 2008.
- Fortier, John (May 17, 2006). "The D.C. colony". The Hill. Archived from the original on November 12, 2010. Retrieved October 10, 2009.
- "DC Sister Cities". D.C. Office of the Secretary. Retrieved August 13, 2019.
- "Twinning with Rome". Ville de Paris. Archived from the original on June 8, 2011. Retrieved February 21, 2010.
- "Friendship and cooperation agreements". Paris: Marie de Paris. Archived from the original on April 3, 2016. Retrieved September 10, 2016.
- "DC & Addis to Become Sister Cities". Tadias Magazine. Retrieved December 6, 2013.
- "General Information". Library of Congress. Retrieved January 1, 2019.
- "2010–2011 School Opening Report". District of Columbia Public Schools. Archived from the original on January 19, 2012. Retrieved November 12, 2011.
- "DC Public School Enrollment Up for Third Straight Year". Office of the State Superintendent of Education. November 7, 2011. Retrieved November 12, 2011.
- Settimi, Christina (July 5, 2007). "Best And Worst School Districts for the Buck". Forbes. Retrieved June 10, 2008.
- Haynes, V. Dion; Bill Turque (May 16, 2008). "Rhee Offers Plan To Improve D.C.'s Troubled Schools". The Washington Post. p. B01. Retrieved June 3, 2008.
- "SY2010-2011 Charter School Profile". D.C. Public Charter School Board. Archived from the original on January 9, 2011. Retrieved January 8, 2011.
- Haynes, V. Dion; Theola Labbe (April 25, 2007). "A Boom for D.C. Charter Schools". The Washington Post. pp. A01. Retrieved July 25, 2008.
- "Table 15. Number of private schools, students, full-time equivalent (FTE) teachers, and 2006–07 high school graduates, by state: United States, 2007–08". National Center for Education Statistics. 2008. Retrieved November 12, 2011.
- "In Your Neighborhood". D.C. Public Library. Retrieved August 14, 2011.
- "DC Tuition Assistance Grant". Consortium of Universities of the Washington Metropolitan Area. Archived from the original on September 28, 2013. Retrieved September 27, 2013.
- Bowman, Inci A. "Historic Medical Sites in the Washington, DC Area". U.S. National Library of Medicine. Retrieved August 17, 2011.
- "Public Road Length". Highway Statistics 2006. Federal Highway Administration. Archived from the original on November 22, 2012. Retrieved September 17, 2012.
- Schrag, Zachary (2006). "Chapter 5: The Bridge". The Great Society Subway. Johns Hopkins University Press. ISBN 978-0-8018-8906-6.
- I-66: Kozel, Scott M. (May 31, 2000). "Interstate 66 in Virginia". Roads to the Future. Retrieved April 22, 2017.I-395:
- "Metro launches Silver Line, largest expansion of region's rail system in more than two decades" (Press release). Washington Metropolitan Area Transit Authority. July 25, 2014. Archived from the original on August 1, 2014. Retrieved August 4, 2014.
- Dawson, Christie R. (August 21, 2009). "Estimated Unliked Transit Passenger Trips" (PDF). American Public Transport Association. Archived from the original (PDF) on August 23, 2011. Retrieved October 10, 2009.
- "About DC Circulator". DC Circulator. Archived from the original on April 15, 2012. Retrieved March 3, 2012.
- "District of Columbia Amtrak Fact Sheet FY 2010" (PDF). Amtrak. November 2010. Archived from the original (PDF) on January 19, 2012. Retrieved July 19, 2011.
- "Union Station gets new bus depot". WJLA-TV. November 15, 2011. Retrieved June 19, 2012.
- Halsey III, Ashley (January 20, 2011). "Washington area tied with Chicago for traffic congestion, study finds". The Washington Post. Retrieved August 15, 2011.
- Christie, Les (June 29, 2007). "New Yorkers are top transit users". CNNMoney. Retrieved July 15, 2008.
- "District of Columbia Commuting Characteristics by Sex". 2010 American Community Survey. United States Census Bureau. Archived from the original on February 12, 2020. Retrieved October 16, 2011.
- "D.C. among top 10 most walkable cities". WTOP. August 8, 2011. Retrieved August 28, 2011.
- McKenzie, Brian (August 2015). "Who Drives to Work? Commuting by Automobile in the United States: 2013" (PDF). American Survey Reports. Retrieved December 26, 2017.
- "History—DC Streetcar". District Department of Transportation. Retrieved April 28, 2013.
- "Dulles Metrorail Project Overview". Metropolitan Washington Airports Authority. Retrieved December 2, 2012.
- "Capital Bike-Share Washington DC / Arlington | PBSC". PBSC Solutions Urbanes. Retrieved June 17, 2016.
- "Bicycle Program". District Department of Transportation. Archived from the original on June 27, 2012. Retrieved September 16, 2012.
- "The Washington Aqueduct System". National Park Service. Retrieved January 5, 2014.
- "General Information". District of Columbia Washington and Sewer Authority. Retrieved January 5, 2014.
- "Welcome to Pepco". January 5, 2014. Pepco. Archived from the original on January 6, 2014.
- Rein, Lisa (April 6, 2010). "D.C. streetcar project may get hung up on overhead wires". The Washington Post. Retrieved January 5, 2014.
- DeBonis, Mike (May 15, 2013). "Plan to bury D.C.'s outage-prone power lines backed by task force". The Washington Post. Retrieved January 4, 2014.
- "Company Profile / History". Washington Gas Light Co. Retrieved January 5, 2014.
- Official website
- Guide to Washington, D.C., materials from the Library of Congress
- Geographic data related to Washington, D.C. at OpenStreetMap
- U.S. Geological Survey Geographic Names Information System: District of Columbia (civil)
- Why is Washington, D.C. Called the District of Columbia?
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