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
Alcatraz Federal Penitentiary as it was conjectured that they drowned in the bay and their bodies swept out into the sea due to the turbulent bay currents. The most violent escape attempt occurred on May 2–4, 1946, when a failed attempt by six prisoners led to the Battle of Alcatraz, also known as the "Alcatraz Blastout". It was carried out by six prisoners; Bernard Coy, Joseph Cretzer, Sam Shockley, Clarence Carnes, Marvin Hubbard and Miran Thompson. They daringly took control of the cell house by overpowering correctional officers, and were able to enter the weapons room, where they then demanded keys to the