The Marina is the city's flat walk, which in San Francisco is a rare and precious thing — a level run along the bay with a fairground palace at one end and an old army fort at the other. The whole way, the Golden Gate is over your shoulder.
About four kilometres, best in the afternoon when the fog's lifted off the water. Start at the Palace of Fine Arts, the domed rotunda left from the 1915 world's fair, and walk the lagoon all the way round — the dome doubles in the water, swans and all. Cross to the Marina Green, the long lawn where the city runs and flies kites, with Alcatraz ahead and the Wave Organ a short spur out on the jetty.
Follow the seawall east past the yacht harbour to Fort Mason, the old army post turned cultural centre, its finger piers now full of galleries and a vegetarian restaurant on the water. Walk out to the pier ends for the bay at eye level, then cut up to Chestnut Street to finish among the cafés, with the 30-Stockton to carry you home.
