United States Penitentiary, Marion

The United States Penitentiary Marion is a federal correctional institution in southern Illinois that combines different security classifications under one administrative umbrella. The facility houses both a medium-security main complex and a separate section for lower-custody inmates.

The federal government opened this facility in 1963 as a successor to the closing prison on Alcatraz Island. For over four decades, the institution held some of the most dangerous offenders in the federal system.

The institution maintains separate Communication Management Units to monitor and control the communications of specific groups of inmates within the federal prison system.

Visitors reach the complex via Interstate 57 south of Marion. General visiting times occur on weekends between late morning and early afternoon.

The complex contains special communication monitoring units that exist in only a handful of federal prisons nationwide. These areas allow authorities to oversee all contact certain inmates have with the outside world.

Location: Illinois

Location: Williamson County

Inception: 1963

Official opening: 1963

GPS coordinates: 37.66310,-88.98420

Latest update: December 12, 2025 22:03