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 Library Alcatraz Library Alcatraz Library was a library for inmates at Alcatraz Federal Penitentiary. It was located at the end of D-Block. On entering Alcatraz, every inmate received a library card and a catalog of books found in the library. An inmates ordered a book by putting a slip with their card in a box at the entrance to the dining hall before breakfast, and a librarian took the order to and from their cell. The library, which used a closed-stack paging system, had a collection of 10,000 to 15,000 books, mainly left over from Alcatraz's army days. Inmates were permitted