Northwest 60th Street - 28%
East Roy Street - 26.04%
East Boston Street - 23.8%
East Highland Drive - 23.6%
Mercer Street - 22.6%
East Boston Street - 22.5%
Mercer Street - 22.4%
East Prospect Street - 22.3%
Helen Street - 22.0%
Ward Street - 21.5%
South Grahm Street - 21.5%
Madison Street - 19%
Queen Anne Avenue (Counter Balance) - 18.5%
James Street - 18.3%
Cherry Street - 17.1%
(There are many blocks in town with 18% to 21% grades.)
SDOT - Steep Streets in Seattle