A hidden bathhouse in one of Stockholm's oldest and busiest neighborhoods is open to anyone who can find it.

An illuminated manuscript comprising the life's work of a lone monk, inexplicably decorated with a portrait of Satan himself.

A magical, if a bit tacky, 1960s castle conjures up medieval fairytales and Greek mythology.

A small island with shimmering pink sands, home to loggerhead turtles and rare plants.

This famous archeological mystery may be an ancient example of movable type.

A quirky bookstore hidden beneath a sea of whitewashed Greek villas.

Replicas of Apollo's leonine stone guard cats still line a sacred row in Greece.

A minotaur, a labyrinth, and a dubious restoration pull in visitors from around the world.

This ancient Greek place of assembly and marketplace is being revealed layer by layer below the modern Athens cityscape.

Perched on a spindly rock spire in a Greek archipelago, this lighthouse would make a perfect wizard's tower.

The hallucinogenic center of the ancient world.

Hidden in a secluded Greek cove is a pristine beach marred only by the rusting smuggler's hulk stranded on its shores.

This pink watchtower served as the seat of the Greek government after independence from the Turks.

An abandoned desert hamlet swallowed up by sand.

A fascist-era rural village abandoned since the early 1980s.

This once-abandoned mansion is now a dreamy event space.

A miniature village lies nearly forgotten in the forest by the side of a major highway.

These imposing walls and towers look more like the ruins of a fortress than a monastery.

The ruins of a medieval monastery named after a type of tree.

This historic building displays the remains of a victim of the devastating 14th-century plague.

One of the greatest movie directors of all time lived and worked in this London flat from 1926 to 1939.

A labyrinth hides in plain sight at each of the city's 270 Tube stations.

Tombstones and enigmatic inscriptions hide within a vault beneath a popular London arts venue.

The "lost friend” is the most famous of the six moai statues that were removed from Easter Island.