A collection of more than 12,000 shoes, displayed in a building shaped like a shoebox.

God's Saharan sandbox of wrath.

One of the most spectacular canyons in the world.

A fortified city, home to a remaining population of five families

An abstract monument to a symphonic composer.

A 250-year-old timepiece-automaton adorned with golden mechanical birds, which still sing to this day.

The oldest museum in Russia is home to a fascinating collection of nearly two million anthropological artifacts and anatomical curiosities.

A subterranean house of worship carved right out of the bedrock.

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

A whimsical bridge adorned with decorative dragons.

This Budapest bar allows drinkers to leave their mark on the walls, floor, and even ceiling.

The mummified right fist of a 1,000-year-old saint-king sits inside an ornate golden reliquary.

Countless stories attempt to explain Poland's mysterious J-shaped trees.

The blood-soaked ruins of the castle where the murderous Blood Countess was walled in alive.

An underground city of salt.

An Austrian house of bones filled with hundreds of intricately painted skulls.

The fairy tale castle of the "fairy-tale king."

Op-art architecture designed for happiness.

Despite attempts by local police to discourage it, Beatles-inspired graffiti has been a means for artists to air grievances for decades.

Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.

Macabre astrological automaton clock dating to the late 1400s.

Looming communist pillar with a Czech twist.

This shop and gallery is a modern-day cabinet of curiosities, unassumingly positioned along an urban thoroughfare.

Two stunning 17th-century libraries and a cabinet of curiosities.