US Penitentiary Administrative Maximum, also known as ADX Florence, the "Alcatraz of the Rockies," and "Supermax," is a modern super-maximum security federal prison located in the foothills of the Rocky Mountains near Florence, Colorado. Opened in 1994, the ADX Supermax facility was designed to incarcerate and isolate criminals deemed as being too dangerous for the average prison system. The majority of prisoners are kept in administrative segregation. They are confined to a specifically designed single-person cell for 23 hours a day. Prisoners are moved around under strict restraints (handcuffed, shackled or both), for their 1 hour time out, which includes showers, exercise, and with privileges, phone calls. Served in their cell, their meals are restricted to foods that can't be used to harm themselves, or create unhygienic conditions.