The works of poetry's biggest names grace the walls of the city of Leiden, all carefully painted by hand.

The highest cold-water geyser in the world.

Walk inside a half mile long crevice right outside the town of Garmisch Partenkirchen.

Sitting in the basement of a castle, the largest wine barrel in the world is bigger than most apartments.

Every hour the doors open to reenact the legend of the heroic mayor who saved his town by drinking a gallon of wine.

Go surfing on this urban wave, "hacked" by local surfers.

The last bastion of Roman presence north of the Alps looms over a German town.

This medieval castle overlooking the Elzbach river looks just like it did hundreds of years ago.

The birthplace of an eccentric alchemist and possible inspiration for the fictional reanimator of monsters.

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

Fantastic views and thousands of love locks.

Daily jousts and dancing barrel makers in Munich's mechanical clock.

The prototype for all Nazi concentration camps.

The world's largest wooden structure.

Erotic art covers the walls of the largest ancient pleasure palace.

The walls and streets of the ancient city are peppered with penises.

The last moments of the ill-fated Pompeiians, frozen forever in plaster.

Two stone columns flank the grand Venice square, but there were supposed to be three.

Pilgrimage site for star-crossed lovers.

Spain's unique Mosque-Cathedral has been a place of worship for both Muslims and Christians throughout its history.

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.

Macabre astrological automaton clock dating to the late 1400s.

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