Alcatraz Federal Penitentiary and the island became a prison of the Federal Bureau of Prisons in August 1934 after the buildings were modernized to meet the requirements of a top-notch security prison. Given this high security and the location of Alcatraz in the cold waters and strong currents of San Francisco Bay, the prison operators believed Alcatraz to be escape-proof and America's strongest prison. Alcatraz was designed to hold prisoners who continuously caused trouble at other federal prisons. One of the world's most notorious and best known prisons over the years, Alcatraz housed some 1,576 of America's most ruthless criminals including Al Capone,
Alcatraz Island August 1934. Alcatraz was designed to hold prisoners who continuously caused trouble at other federal prisons. At 9:40 am on August 11, 1934, the first batch of 137 prisoners arrived at Alcatraz, arriving by railroad from the United States Penitentiary in Leavenworth, Kansas at Santa Venetia, California, before being escorted to Alcatraz, handcuffed in high security coaches and guarded by some 60 special FBI agents, U.S. Marshals and railway security officials. Most of the prisoners were notorious bank robbers and murderers. The prison initially had a staff of 155, including the first warden James A. Johnston and associate warden J.