This series of Scottish caves has no clear purpose other than baffling historians.

A golden egg-shaped sauna in the Arctic tundra.

Micro-nation based around a nine-story high illegally built tower.

A series of modernist treehouse hotel rooms grace the outskirts of an Arctic forest.

A stunning silver lining to global warming's gloomy cloud.

A gigantic statue of a Russian soldier watches over the ancient city of Plovdiv, a prominent reminder of the Soviet period in Bulgaria.

In a long-dry lake bed, these groups of massive stone pillars bear a striking resemblance to clumps of everyone's favorite fungi.

The ceiling of Prohodna Cave in northern Bulgaria affords a peek at the sky via two deity-sized-eye-shaped holes.

Woven tree art gives this towering Australian woodland a touch of mystical whimsy.

This series of rope-style bridges brings visitors into a jungle layer that is usually reserved for birds and monkeys.

A cozy bookstore and coffee shop in the heart of Cartagena's Old City.

The world's tallest palm trees look like the whimsical kind of plant you'd find in a Dr. Seuss story.

Colorful lights and mirror-like brine pools create trippy illusions within the historic mine.

Unparalleled stargazing, one of Colombia's best observatories, and a swimming pool can all be found in the middle of this ancient tropical forest.

Enchanting cave with a river crashing through the roof.

An explosion of natural color known as "the river that ran away from paradise."

A sharp sculpture made of thousands of pieces of jagged glass.

This secret coastal village is studded with pastel-colored houses all piled on top of one another.

An alien landscape on the banks of the Aegean Sea.

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

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

The world's largest bust sculpture celebrates the Hindu deity, Shiva.

The world's largest human gathering is held at the confluence of three sacred rivers, one of which is mythical.

This 11th-century temple gave rise to the word "juggernaut," as well as some mysteries that defy scientific explanation.