The United States Penitentiary, Florence ADX, is a supermax prison located in Florence, Colorado. It is designed to hold the most dangerous criminals in the United States, including terrorists and organized crime leaders. The facility features high-security measures, including solitary confinement and strict surveillance, to ensure the safety of both staff and inmates. Opened in 1994, Florence ADX is part of the Federal Bureau of Prisons and is known for its harsh conditions. Inmates are often kept in their cells for 23 hours a day, with limited access to recreational activities. Notable inmates have included Tamerlan Tsarnaev and Ted Kaczynski.