Alcatraz Federal Penitentiary Alcatraz Federal Penitentiary The Alcatraz Federal Penitentiary or United States Penitentiary, Alcatraz Island (often just referred to as Alcatraz or The Rock) was a maximum high-security federal prison on Alcatraz Island, off the coast of San Francisco, California, which operated from August 11, 1934, until March 21, 1963. The main prison building was built in 1910–1912 during its time as a United States Army military prison; Alcatraz had been the site of a citadel since the 1860s. The United States Disciplinary Barracks, Pacific Branch on Alcatraz had been acquired by the United States Department of Justice on October 12, 1933,
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