In which US state is San Quentin prison?

San Quentin State Prison (SQ) is a California Department of Corrections and Rehabilitation state prison for men, located north of San Francisco in the unincorporated town of San Quentin in Marin County, U.S.

Opened in July 1852, San Quentin is the oldest prison in California. The state's only death row for male inmates, the largest in the United States, is located at the prison. It has a gas chamber, but since 1996, executions at the prison have been carried out by lethal injection, though the prison hasn't performed an execution since 2006. The prison has been featured on film, video, and television; is the subject of many books; has hosted concerts; and has housed many notorious inmates

The correctional complex sits on Point San Quentin, which comprises 432 acres (1.75 km2) on the north side of San Francisco Bay. The prison complex itself occupies 275 acres (1.11 km2), valued in a 2001 study at between $129 million and $664 million.

As of October 30, 2013 the prison had a design capacity of 3,082 but a total institution population of 4,223, for an occupancy rate of 137 percent. It has Level I ("Open dormitories without a secure perimeter") housing; Level II ("Open dormitories with secure perimeter fences and armed coverage") housing; a Reception Center (RC) which "provides short term housing to process, classify and evaluate incoming inmates"; and a Condemned unit.