Snapped this on a recent visit to San Francisco. Alcatraz, also known as 'The Rock', is a former Federal prison planted firmly on a small island in the middle of San Francisco Bay. Once the home of some infamous people such as Al Capone, George "Machine Gun" Kelly and Robert Stroud, who was better known to the public as the "Birdman of Alcatraz," it is now one of the main tourist attractions in San Francisco.