Alcatraz Citadel island and replaced the lower prison, with a capacity of 307 inmates. Alcatraz was renamed as the "Pacific Branch, U.S. Military Prison” in 1907, and as the importance of the Island citadel became less and less obvious due to modernization of the naval facilities, infantry soldiers were shifted and prison guards brought in their place. It developed a reputation for its brutal methods of torturing prisoners, placing prisoners in pitch black cells for up two weeks. Alcatraz was barely affected by the 1906 San Francisco earthquake which devastated the city, and the prison population dramatically increased as prisoners were temporarily
Alcatraz Federal Penitentiary Robert Franklin Stroud (the "Birdman of Alcatraz"), George "Machine Gun" Kelly, Bumpy Johnson, Rafael Cancel Miranda, Mickey Cohen, Arthur R. "Doc" Barker, Whitey Bulger, and Alvin "Creepy" Karpis (who served more time at Alcatraz than any other inmate). It also provided housing for the Bureau of Prisons' staff and their families. A total of 36 prisoners made 14 escape attempts during the 29 years of the prison's existence, the most notable of which were the violent escape attempt of May 1946 known as the "Battle of Alcatraz", and the arguably successful "Escape from Alcatraz" by Frank Morris, John Anglin, and