San Francisco is outside California.
The Alcatraz Federal Penitentiary or United States Penitentiary , Alcatraz Island ( often just referred to as Alcatraz ) was a maximum high-security federal prison on Alcatraz Island , 1.25 mi off the coast of San Francisco , California , which operated from 1934 to 1963 . Lyft is a transportation network company based in San Francisco , California . San Francisco ( initials SF ) ( [ sæn_frənˈsɪskoʊ ] , Spanish for Saint Francis ; Spanish : [ san franˈsisko ] ) , officially the City and County of San Francisco , is the cultural , commercial , and financial center of Northern California . San Francisco is also the headquarters of five major banking institutions and various other companies such as Levi Strauss & Co. , Gap Inc. , Salesforce.com , Dropbox , Reddit , Square , Inc. , Dolby , Airbnb , Weebly , Pacific Gas and Electric Company , Yelp , Pinterest , Twitter , Uber , Lyft , Mozilla , Wikimedia Foundation , Craigslist and Weather Underground . The San Francisco Bay Area ( referred to locally as the Bay Area ) is a populous region surrounding the San Francisco and San Pablo estuaries in Northern California .