Ex London Transport RML2279, CUV279C, dating from 1965, a long way from home. Now a tour bus, suitably modified, it was only identifiable (to me anyway) as it miraculously retains it's UK registration plate.

Note the tram (streetcar) tracks in the foreground on the San Francisco F line.

Photo taken by Steve Piper, Tuesday 30 June 2009, Fisherman's Wharf, San Francisco