San Francisco Bay is the artificial and flat Treasure Island, site of the 1939 Golden Gate International Exposition. From the Second World War until the 1990s, both islands served as military bases and are now being redeveloped. Isolated in the center of the Bay is Alcatraz, the site of the famous federal penitentiary. The federal prison on Alcatraz Island no longer functions, but the complex is a popular tourist site. Despite its name, Mare Island in the northern part of the bay is a peninsula rather than an island. San Francisco Bay is thought to represent a down-warping of the Earth's crust between
Battle of Alcatraz cellblock. Joe Cretzer was a west coast gangster and member of the Cretzer-Kyle Gang. In 1940 he was sentenced to 25 years for murder. After two escape attempts in the first months of his incarceration, one of which resulted in another murder charge, he was transferred to Alcatraz. In May 1941, Cretzer, Shockley and two other convicts made an escape attempt from one of the prison's workshops. Carnes was the youngest prisoner to reside at Alcatraz, having been convicted of murder in 1943 at the age of 16. He made a number of escape attempts and by 1946, when he