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
June 1962 Alcatraz escape attempt to death by guards because he wouldn't help investigators locate his brothers. A 2014 study of the ocean currents by scientists at Delft University and the research institute Deltares indicates that if the prisoners left Alcatraz at 11:30 pm on June 11, they could have made it to Horseshoe Bay just north of the Golden Gate Bridge, and that any debris that were released into the bay would have floated into the direction of Angel Island, consistent with where the paddle and belongings of the prisoners' was actually found. A 2015 History Channel documentary presented further circumstantial evidence gathered over