The healing properties of this well attracted royals and commoners throughout the Middle Ages.

The remains of the concrete ship can be seen during low tide.

The next-door homes of two very different musicians, George Frideric Handel and Jimi Hendrix.

The wreckage of an old coastal trading vessel is only visible at low tide.

This Scottish castle has witnessed clan rivalries, Jacobite uprisings, whisky smuggling, and more.

This centuries-old hotel hides a network of secret cellars and passages once used by smugglers.

One fisherman has used his love of pebbles and shore to create a crazy garden of rocky art.

One of the oldest libraries in England, and one of the last of the great medieval chained collections.

Part museum, part piece of Arthurian-inspired history, this stately hall attracts King Arthur fans from miles away.

These medieval tunnels provided water to the city above through centuries of civil war and plague.

This network of narrow, medieval passages has the most delightful name.

This unique bridge curls up like a caterpillar to let boats pass and then unfurls again to span a small canal.

A harem-inspired Moorish fantasy design in a Victorian-era Welsh castle.

A glacial pothole was once a hideout for a notorious Scottish outlaw.

A mysterious artist-run cabinet of curiosities and library.

This grisly headstone doesn’t seem to be resting in peace.

More than 500 unique and specially designed cases collected by D.C.'s "Harmonica Case Man."

A neo-Gothic church built to thank God for saving the Emperor of Austria from an assassination.

One of Canada's oldest museums, the beautiful Redpath has been serving up Natural History and Ethnography since 1882.

Japan's longest-running music festival takes place on an isolated butterfly-shaped island.

This cemetery overlooking the Benbulben rock formation is the final resting place of one of Ireland's most beloved poets.

A mysterious Neolithic tomb is perched along the edge of a modern golf course.

An abandoned faux-pub made famous by a Guinness commercial.

Famed for its pie, this eatery has a hidden tunnel that allowed Catholics to secretly walk to church during the Reformation.