101 Spear (at Mission)
Built as a Works Progress Administration project, the Rincon Annex post office is among the city's finest links to a glorious art deco past. When the Rincon Center shopping and office complex was built in 1978, developers were required to preserve the splendid murals depicting California's history as executed by Russian artist Anton Refregier. Begun in 1941, his lobby frieze was finally completed in 1948, after being interrupted by World War II. The gorgeous work speaks for itself, but historical graphics in the lobby provide plenty of information about the paintings. Plus, there are several display cases that contain relics of early San Francisco.