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.

A spectacular cave and a beguiling lake.

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

Tall columns of volcanic basalt make up this improbable-seeming rock formation.

This network of conjoined cellars was riddled with traps and supposedly allowed the townspeople to pretend their homes were deserted.

This unusually shaped mountaintop tower looks like a UFO floating over the city.

A crucified and bearded female saint.

The deepest sinkhole in Central Europe comes with a grisly tale and an unusual nickname: “The Stepmother Abyss.”

Enormous sandstone towers loom within a Czech forest.

This walkway is so narrow it needs its own light to stop pedestrian traffic jams.

The world's greatest slide descends 18 stories from this looping mountaintop viewing platform.

This former quarry is now a picturesque gorge that hides a sunken lake.

An Orwellian sculpture with eyeball cameras watches passersby.

A spiral staircase twists to the top of this unusual Czech lookout tower.

What looks like a crashed Zeppelin is actually a bright, airy reading room perched atop a modern museum.

Europe's largest natural bridge has a 19th century royal chateau built into its side.

Thirty creepy ghosts now inhabit this decaying 14th-century church.

A steampunk-styled three-floor factory churning out art, activism, and electronic beats.

This dramatic landscape hidden on the Isle of Skye looks as though you've stepped into the magical realm.