Greetings from San FranciscoSan Francisco, the City by the Bay, rose from a small Spanish settlement to become one of the largest and most unique cities in the United States. Vintage postcards from the 1900s to the 1960s showcase the Golden Gate Bridge (one of the Seven Modern Wonders of the World), cable cars as they make their way up Market Street, Alcatraz Island and the prison that housed public enemies like Al Capone, Machine Gun Kelly, and Robert Franklin Stroud (the