Supermax prisons are high-security facilities designed to house the most dangerous and violent offenders. These prisons feature strict security measures, including reinforced walls, limited inmate movement, and constant surveillance. Inmates often spend 23 hours a day in solitary confinement, which is intended to prevent violence and maintain order. The term "Supermax" is short for "super-maximum security," and these prisons are used to isolate inmates who pose a significant threat to staff and other prisoners. Notable examples include the United States Penitentiary, Florence ADX in Colorado, which houses infamous criminals and terrorists.