Alcatraz Federal Penitentiary (high-security isolation prison)

Alcatraz Federal Penitentiary operated on Alcatraz Island from 1934 to 1963 as a maximum-security federal prison designed to house inmates considered particularly dangerous or escape-prone. The facility was known for strict isolation practices and held well-documented inmates such as Al Capone and George 'Machine Gun' Kelly. The island is now managed by the National Park Service and is a historic site and museum.