[snrplfth]

The impression I'm getting from this and other comments is that San Francisco is basically a bunch of small mountains where people get mugged.

I live in a pretty flat city, but there's so much transit in the inner city (<8 minute frequencies most of the day) that seniors just take it everywhere. It's safe, it's warm, there's room for grocery carts, there's special seating for the mobility-impaired....maybe it's just implementation.