Canton Avenue is 630 ft (190 m) long (the hill is about 213 feet long) and is claimed to include a 37% grade 21 feet (6.4 m) long.[4][5][6] The
Guinness Book of World Records says
Baldwin Street, in Dunedin, New Zealand, is the world's steepest street with a gradient of 34.8%.[7] This record is disputed; Pittsburgh news and international media have claimed Canton Avenue is the steepest street in the world.[8][9][10] The United States record is also disputed, as Bradford Street in San Francisco includes a 39% grade nine meters long[11] and
Waipio Valley Road has sections as steep as a 45% grade. [12][13][14][15]
The
National Map says the steep 213 feet of Canton Avenue averages less than 30%. The map's elevations can be off by a foot or two; probably Pennsylvania's LIDAR surveys done in the last few years can do better. Google Earth says the street averages 29% for 212 feet.
^An article in the Pittsburgh Press on 11 January 1987 cites information compiled by the Surveys Division and the Snow and Ice Control Program, Dept of Public Works, that Canton Street has a steepness of 37 percent.