According to the Ordnance Survey, Vale Street is the steepest street in England, with a 21.81 degree incline. When there's ice on the road, the residents tie their cars to lamp posts.
It's more impressive looked at from the bottom, with all the gouges in the road where car exhaust pipes have caught as it levels off, but I was not [incoming pun] inclined to go and look because then I'd have had to walk back up again.