St. Mary's Asylum was isolated and abandoned before being converted into a Bed and Breakfast.

A well-preserved 2nd century fort where moles are the archaeologists.

A museum and gardens with unusual plants and a history of progressive programming for the blind.

A vortex fountain that seems to rise out of the ground.

This hidden natural fountain issues forth a steady supply of supposedly healing water that tastes like rotten eggs.

This lovely little burbling creek is actually a deadly waterway that has dragged down everyone who ever set foot in it.

Where Agatha Christie mysteriously disappeared in 1926.

An abandoned 18th century manse looks like something out of an Indiana Jones movie.

An enigmatic natural rock formation with a manmade passage cut through the center.

The storied English village that pretended to be insane inspired NYC's nickname and the fictional namesake in the DC Comics universe.

A Scottish manor with a history of mysterious fires, magic, and eccentric tales

Built during the Scottish boom in the oil industry, the village was never inhabited.

The last inhabitants of one of the U.K.'s most remote islands were evacuated in 1930.

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

A curious collection of mechanical moving figures.

A giant pineapple, a symbol of hospitality, and an amazing vacation rental option.

Ruined castle with subterranean vaulted Goblin Ha' or "Goblin Hall."

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

360° views of the city plus five floors of optical illusions and hands-on science.

A 30-acre garden inspired by the principles of modern physics.

A 550-square-meter micro-nation off the coast of Britain.

A 19th century artistocrat's mansion, turned into a library, hidden in a modern library.

The sculptural remains of the last home of a legendary Dada artist.

This hospital once pioneered the use of electroencephalograms, but fell into maltreatment, abuse, and eventual abandonment.