ADX Florence was built for inmates the U.S. prison system could not safely hold anywhere else, from cartel leaders and spies ...

Hidden in the Colorado mountains, ADX Florence is considered the most secure prison in the United States. Designed to hold terrorists, cartel leaders, mob bosses, and some of the country's most ...

Add Yahoo as a preferred source to see more of our stories on Google. Eric King served almost two years at the federal super-maximum security prison ADX Florence in Colorado. ADX is often described as ...