San Quentin and Folsom state prisons are two of the toughest institutions in California. These prisons - which opened in the mid-1800s - have been home to thieves, con artists, and serial killers. Photos from San Quentin show how average every day life could be, while construction photos from Folsom show how prisoners were forced to build their own walls.
These facilities still operate today, and collectively are home to about 6,000 prisoners. They are some of the largest prisons in the country, were used as the backdrop for many crime dramas - both fictional and true. In particular, San Quentin State Prison has proved a fascination for many writers and filmmakers. They've housed some of the most notorious criminals in US history. Some of the famous inmates of San Quentin include Charles Manson, Charles Ng, and the Tool Box Killers.
These photos in California's hardest prisons will give you a little insight into what life was really like inside these jails, from the turn of the century to modern times.