A Red Cross memorial museum at the site of the Niš concentration camp that operated for four eventful years during World War II.

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

Even drowned in an ocean of toxic waste, the remnants of this Romanian village stand tall.

This Transylvanian church has changed its denomination four times.

Some call this eerie forest of crooked trees the "Bermuda Triangle of Romania."

The Natural History Museum that time forgot.

This massive underground salt mine now holds a sci-fi theme park in its depths.

Romania's "Red Ravine" is a little-known natural wonder that bears a resemblance to the Grand Canyon.

Once the legendary capital of the Dacian Kingdom, this city has been reduced to mere ruins.

This fairy-tale castle would make Dracula (who is said to have been imprisoned there) jealous.

A collection of items from a way of life that no longer exists.

Space-age monument to an early 20th-century uprising.

A surreal statue honoring Prague's favorite literary son.

A delightful museum entirely dedicated to the tiny homes of dolls.

The largest toy museum in Poland showcases Europe's history of childhood.

A national collection of Communist-era musical posters.

Large, airy hallways hide within an impenetrable fortress that beckons urban explorers.

A chain of 16 wondrous lakes formed as a result of the gradual dissolution of soluble layers of bedrock.

A musical instrument played by the sea.

Where the lovelorn find a home for their sentimental keepsakes.

Once a state-of-the-art tuberculosis treatment spa, these ruins are now ruled by paintball players.

Legend has it fairies gathered at the site of this medieval castle.

This huge metal monument is slowly being stripped to its concrete skeleton.

This scale model of our solar system hid in plain sight for years before a physics team sought out all the planets.