The Alcatraz prison also known as the Rock was known to be a secure and inescapable prison but is now closed.
The only other Prison I know about that is considered inescapable and that is still in operation today is the ADX Florence where prisoners have only a tiny window in there cells and stay in there cells for at least 23 hours per day with only 1 hour outside in a cage for recreation.
Their showers are in the cells and there food is brought to them through slots in the doors of the cells.