The hermits of Karoulia protect their asocial lifestyles by living on the vertical face of a treacherous precipice.

An alien landscape on the banks of the Aegean Sea.

These ruins in Volvi were once at the intersection of the Eastern and Western Worlds.

Cave on extinct volcano, once home to famous mathematician Pythagoras.

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

Swarms of dainty flying insects swarm into the Petaloudes Valley to get busy.

A Bronze age settlement on the Greek island of Santorini might have been the inspiration for Plato's Atlantis.

This legendary city has been a tourist attraction for centuries.

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

A spectacular cave and a beguiling lake.

The hallucinogenic center of the ancient world.

Monasteries on rock pillars, once accessible only by frayed ropes.

Despite being pillaged and destroyed a number over times down the centuries, this historic church still sort of stands.

A grand Yugoslav memorial to the group of partisans who fought and died resisting western Serbia’s Nazi occupation.

This spaceship-like Serbian monument reaches for the stars in celebration of the fallen fighters of fascism.

This 14th century castle withstood years of battle but is now sliding off the hills into the Danube.

A beautiful mountaintop mausoleum devoted to a Montenegrin icon can't seem to make everyone happy.

These historic defenses ensured the city within would survive hundreds of years of occupations, sieges, and invasions.

Castle and secret tunnel withstood a siege until its owner was killed by the Holy Roman Empire, while sitting on the toilet.

This massive subterranean fissure is known as the "underground Grand Canyon."

Martin Bricelj Baraga's monolithic sculpture measures the blueness of the sky, and changes color to match it.

This one-time health resort was used by aristocrats around the world.

Small Island off the coast of Greenland.

This remote research station sits amid the second-largest ice sheet on the planet.