There's a mini version of Iguazu Falls hidden in the Balkans, and it's got a rope swing.

Bridge that died in war and was resurected.

This ancient theater was once the home of fierce gladiatorial battles.

Historic medieval fortified city in southwest France.

The world's tallest bridge is also possibly the most elegant.

Hundreds of prehistoric stones, arranged in perfect lines in a French field.

This French ghost town from World War II has been left as a memorial to German atrocities during World War II.

The world's largest reflecting pool is just two centimeters deep.

The spectacular history of spectacles on display.

Brussels' favorite peeing boy has a sister.

A little sculpture with a large wardrobe.

This collection of over 50 murals celebrates Brussels' rich history as the self-proclaimed home of the "comic strip."

Cozy basement bar sports an inventory of over 2,000 beers.

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.

The world's only museum devoted to the wonders of fluorescence.

This Paris art space celebrates the creativity and ingenuity that springs from abject poverty, especially in Africa.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

This massive library holds what was once the largest book collection in the world.

Home to the "Rat King" of Nantes and other wonders of the natural world.

Massive puppet-automaton machines created by French artist collective Machines de l’Ile.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

Louise Bourgeois' 30-foot-tall steel spider sculpture.