San Quentin State Prison 1 Main St, San Quentin, CA94964 Built in 1852, San Quentin State Prison is the state of California's oldest correctional institution. Located on the San…More Francisco Bay waterfront just east of Larkspur Landing, the 432-acre prison is home to the state's only gas chamber and death row. Death penalties are handled by injection these days. The prison houses more than 5,000 inmates. Many nonprofits and other civic organizations in Marin County volunteer in various capacities at the prison, including academic tutors and even acting coaches. In recent years, there has been a movement to nullify the death penalty and even close the antiquated facility and sell off the land.