England's Tower of London served as an operating prison from the year 1100 all the way up to 1952. It was rebuilt in the late 13th century but has stayed mostly the same ever since.
Cellular Jail, located on India's Andaman Nicobar Islands, was used in the early 20th century by the British mainly to exile political dissidents who were fighting for India's independence.
East Jutland State Prison opened a little over 10 years ago in Enner Mark, Denmark. Its clean, simple design masks high security, including infrared cameras, motion sensors, and fingerprint scanners.
In Overloon, Netherlands, the Juvenile Pavilion youth detention center uses an open design plan and borrows the natural-wood feel of the surrounding environment to keep inmates engaged with the outside world.
The Austrian prison Garsten Abbey used to function as a monastery up until 1851, at which point it began running as a prison. Its Baroque architecture makes it one of the more sophisticated-looking facilities in the world.
Scenic Bastoy Prison, located on a private island about 35 miles northwest of Halden, is another open prison that gives prisoners access to farming, fishing, skiing, tennis, and horseback riding.
Fremantle Prison, located in Western Australia, was decommissioned in 1991 after a 136-year run. It is now listed as UNESCO World Heritage Site.
Chillon Castle is located on Lake Geneva, in Switzerland. It functioned as a prison during the Wars of Religion in the 16th century and later was turned into a weapons depot and outpost.
If not for the heavy locking doors, Her Majesty's Prison (or HMP) Parc, in Wales, could pass for a public school. It offers numerous classes, a gymnasium with hot showers, pool tables, and ping-pong tables.
Villa Sbertoli, an Italian prison and mental hospital, was built in the 18th century and featured vaulted ceilings, interior balconies, and colorful frescoes.
Norway's Halden Prison lets inmates cook, play video games, shoot hoops, and sleep on plush beds. Rooms look more like college dorms than cells. The idea is to treat convicts like people, so they will re-enter society in a healthy mindset.
Austria's Justice Center was designed by Joseph Hohensinn to let in ample light. There are two inscriptions by the entrance, each affirming inmates' right to dignity and humanity.
