Canton Avenue, in Pittsburgh, Pennsylvania's Beechview neighborhood, is the steepest officially recorded public street in the United States. 
Canton Avenue may be steeper, but the Guinness Book of World Records says Baldwin Street in New Zealand is the world's steepest. Baldwin Street is 1,150 ft (350 meters) long and is said to include a grade of 35%. Canton Avenue is 630 ft (192 meters) long and is claimed to include a 37% grade of unknown length.
Coordinates: 40°24′32″N 80°01′48″W / 40.409°N 80.03°W / 40.409; -80.03