Marunouchi (丸の内) is a commercial district of Tokyo located in Chiyoda between Tokyo Station and the Imperial Palace. The name, meaning "inside the circle", derives from its location within the palace's outer moat. It is also Tokyo's financial district and the country's three largest banks are headquartered there.
In 1590, before Tokugawa Ieyasu entered Edo Castle, the area now known as Marunouchi was an inlet of Edo Bay and had the name Hibiya. With the expansion of the castle, this inlet was filled, beginning in 1592.
A new outer moat was constructed, and the earlier moat became the inner moat. The area took the name Okuruwauchi ("within the enclosure").
Daimyōs, particularly shinpan and fudai, constructed their mansions here, and with 24 such estates, the area also became known as daimyō kōji ("daimyō alley"). The offices of the North and South Magistrates, and that of the Finance Magistrate, were also here.
Those moved in 1890, and Iwasaki Yanosuke, brother of the founder (and later the second leader) of Mitsubishi, purchased the land for 1.5 million yen. As the company developed the land, it came to be known as Mitsubishi-ga-hara (the "Mitsubishi Fields").
Much of the land remains under the control of Mitsubishi Estate, and the headquarters of many companies in the Mitsubishi Group are in Marunouchi.
The government of Tokyo constructed its headquarters on the site of the former Kōchi han in 1894. They moved it to the present Tokyo Metropolitan Government Building in Shinjuku in 1991, and the new Tokyo International Forum and Toyota Tsusho Corporation now stands on the site. Nearly a quarter of Japan's GDP is generated in this area.
Much of the area was damaged in the deadly 1974 Mitsubishi Heavy Industries bombing.
|Address||Alternative name||Image||Height(m)||Number of floors||Built|
|5-1 Marunouchi 1||Shin Marunouchi Building||198||38||2007|
|4-1 Marunouchi 2||Marunouchi Building||179||37||2002|
|6-1 Marunouchi 2||Marunouchi Park Building||170||34||2009|
|7-3 Marunouchi 2||Tokyo Building||164||33||2006|
|4-5 Marunouchi 1||Mitsubishi Trust & Banking Head Office||148||30||2003|
|1-2 Marunouchi 2||Meiji Yasuda Life Building||146||30||2004|
This section needs additional citations for verification. (December 2009)
Marunouchi also houses the Japan offices of Aeroméxico ( Pacific Century Place Marunouchi),  Bain & Company, Bayerische Landes Bank, Bloomberg, First National Bank of Boston, BT Group, Citigroup, Banca Commerciale Italiana, Deloitte Touche Tohmatsu, Bank of India, JPMorgan Chase, KPMG, Latham & Watkins, Mellon Bank, Morgan, Lewis & Bockius, Morrison & Foerster, NatWest Group, Nikko Cordial, Nikko Citigroup, Rabobank, Bank Negara Indonesia, Overseas Union Bank, Philadelphia National Bank, PricewaterhouseCoopers, Ropes & Gray, Royal Insurance, Standard Chartered Bank and Standard & Poor's. 
Chiyoda Board of Education operates public elementary and junior high schools. Chiyoda Elementary School (千代田小学校) is the zoned elementary of Marunouchi 1-3 chōme.  There is a freedom of choice system for junior high schools in Chiyoda Ward, and so there are no specific junior high school zones.