Alcatraz Island (sometimes informally referred to as simply Alcatraz or by its pop-culture name, The Rock) is a small island located in the middle of San Francisco Bay in California, United States. It served as a lighthouse, then a military fortification, then a military prison followed by a federal prison until 1963, when it became a national recreation area. The first European to discover the island was Juan de Ayala in 1775, who charted the San Francisco Bay and named the island "La Isla de los Alcatraces", which means "Island of the Pelicans".
