This tiny island featuring 9th-century Viking ruins is only accessible at low tide.

Britain's only herd of free-ranging reindeer.

The remains of a grand castle that may have inspired Bram Stoker's Dracula.

A remarkably well preserved tower dating all the way back to the Iron Age.

A mysterious monument where a woman who records say never existed was burnt alive for being a witch.

Accessible only at low tide, the deserted island is dotted with World War II ruins.

The ruins of this gorgeous clifftop castle look like something from a fantasy novel.

This castle was established by the 4th Duke of Montrose and is connected to the Buchanan Clan.

The most iconic structure in Scotland has been home to bishops, colonels, and Sean Connery characters.

This astonishingly geometric cave has inspired everyone from Jules Verne to Pink Floyd.

Giant naked man on a hillside.

Besieged by war, this castle ruin has crumbled into a peaceful picnic spot.

Famously misunderstood wonder of the ancient world

This South London cemetery holds the remains of more than 15,000 people.

Kings Cross Station pays tribute to its role in Britain's best-selling book series.

This churchyard arbor is surrounded by hundreds of gravestones placed there by author Thomas Hardy.

London's creepiest cemetery was once the site of dueling magicians and mobs of stake-carrying vampire hunters.

What was once England's second-richest abbey is now a haunting ruin.

An abandoned World War II tank left to rust in the downland.

The dramatic remains of an abandoned farmhouse sit high on the edge of a remote hillside.

The remains of a remote village that once housed over 1,200 dam workers and their families.

These ancient ruins were the final resting place of King Henry II's mistress.

On this Puerto Rican island, many abandoned naval ammunition bunkers sit open while a few have been padlocked by locals as personal storage.

Invading U.S. troops were first seen from this now-abandoned tower, leading to the Spanish-American War.