Alcatraz Prison.

Alcatraz was designed to detain prisoners who were constantly causing problems at other federal prisons. One of the most notorious and best-known prisons in the world for many years, Alcatraz housed 250 of America's most ruthless criminals, including Al Capone, Robert Franklin Stroud (the Alcatraz birdwatcher), Bumpy Johnson, Rafael Cancel Miranda,[1] Mickey Cohen, Arthur Baker, James "Whitey" Bulger, and Alvin Karpis (who served longer at Alcatraz than any other inmate). It also provided housing for Bureau of Prisons staff and their families. A total of 36 prisoners made 14 escape attempts during the prison's 29-year existence, the most notable of which was the most violent escape attempt in May 1946 known as the "Battle of Alcatraz", and arguably the successful "Escape from Alcatraz" by Frank Morris, John Anglin, and Clarence Anglin in June 1962 in one of the most intriguing escapes ever conceived. Faced with high maintenance costs and a poor reputation, Alcatraz closed on March 21, 1963.

The three-story cell house included the prison's four main blocks, Block-A, Block-B, Block-C, and Block-D, the warden's office, the visiting area, the library, and the barber shop. The prison cells measured 9 feet (2.7 m) by 5 feet (1.5 m) by 7 feet (2.1 m) high. The cells were primitive and lacked privacy, with a bed, a desk, and a sink and toilet at the back of the wall, with little furniture except a blanket. African Americans were segregated from the rest in designated cells due to racial abuse being prevalent. D-Block housed the worst inmates and five cells at the end of it were designated as "The Hole" where misbehaving prisoners were sent for a period of time to be punished, often brutally. The mess hall and kitchen were outside the main building in an extended section where prisoners and staff ate their three meals a day together. Alcatraz Hospital was above the mess hall.

The prison corridors were named after major streets in the United States such as Broadway and Michigan Avenue. Working in the prison was considered a privilege for the inmates and many of the best inmates were employed in the Industrial Model Building and the New Industries Building during the day, actively involved in providing, for the militia, many jobs such as sewing and carpentry and doing various maintenance and laundry activities.

The main prison building was built between 1910 and 1912, at which time it was a military prison of the United States Army; Alcatraz was a citadel from 1860. The United States disciplinary headquarters, the Pacific Branch on Alcatraz was acquired by the United States Department of Justice on October 12, 1933, and the island became a Federal Bureau of Prisons prison in August 1934, after the buildings were modernized to meet the requirements of a first-class security prison. Given this high security and Alcatraz's location in the cold waters and strong currents of San Francisco Bay, the prison operators believed that Alcatraz was escape-proof and the strongest prison in America.