They are among the most secure places on earth -- hard to get into, and nearly impossible to get out of.
They're called supermax prisons. There are 31 of them around the country, and one of the biggest is the ADX supermax prison in Florence, Colo. It's the only federal supermax in the country; the others are state prisons.
The ADX Florence prison is home to about 500 of the most dangerous criminals in the country. Almost all inmates have been transferred from other facilities, where they...Full Story