This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

This Hungarian castle was built out of cardboard and wood until it proved so popular that it got upgraded to stone.

Once the home of a hermetic monk, this cave now houses a small church.

A museum in the childhood house of a medical pioneer.

A series of caves under Castle Hill that once held the prisoner Vlad Tepes, better known as Count Dracula.

Built in 1870 at the bridge that connected Buda and Pest, this spectacular incline railway was almost lost forever during World War II.

Mountain where Jesus was first tempted by the Devil.

Gaze upon chocolate sculptures depicting everything from chariot races to Gaudí's famous church at this shrine to sweets.

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

Construction of Barcelona’s iconic (but controversial) church was finally completed in 2026—a century after the death of its architect.

An underground city of salt.

The former Nazi Germany concentration camp stands as a museum to remember this dark chapter in European history.

The silly symbol for an underground protest group is now scattered around the city.

A church of bones, decorated with 40,000 human skeletons.

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

The history of occult science is turned into a creepshow at this lurid Prague tourist attraction.

A Jenga-style cylindrical tower of books that appears to go on forever.

A surreal statue honoring Prague's favorite literary son.

The hidden lair of an alchemist rediscovered in a 2002 flood.

An eerie, existential museum dedicated to the author of "The Metamorphosis."

A bust of Franz Kafka spins in pieces, reflecting the writer's inner torment.

Looming communist pillar with a Czech twist.

This valley of hot springs and boiling mud pots is home to the record-holding "Geysir," which originated the English word.

A charmingly eccentric magma chaser presents his complete history of the island's eruptions since 1947, in cinematic form, just for you.