One of the world's most isolated, grim and forbidding prisons is located in Dartmoor, on the lonely Devonshire moors of England.

High-walled Dartmoor Prison was built of local granite during the Napoleonic Wars by the force labor of French prisoners-of-war. It opened in 1809.Since then, the virtually escape-proof prison has been home to numerous murderers, thieves, forgers and criminals. For a period during the War of 1812 between Great Britain and the United States, Dartmoor held a group of American naval prisoners-of-war, who staged a violent uprising there in 1815.

Today, after 185 years, the dreaded Dartmoor is still one of the most secure of Britain's prisons.