Some years ago I lived in Prescott AZ in a hillside community, at the top of the steepest paved road in the city, a 300' climb at a 15% grade. Some cycling neighbors called it "Effing Hill," some saw it as a training opportunity. There were lots of climbs in the area, in the Bradshaw Mts, but most were the typical Western grades not exceeding 6%.
I liked the view there, but will never live at the top of such a hill ever again.