Dancing skeletal figures pay homage to a medieval mural destroyed during World War II.

The site of a concentration camp where inmates were made to take part in one of the largest counterfeiting operations in history is now hauntingly empty.

This German bone house contains the remains of some 20,000 souls.

These 18th century gardens tell a rocky story of the son of Odysseus.

What was once thought to be a wellspring of unicorn bones is actually just a prehistoric burial site.

Gardens representing parts of Asia, Europe, and the Mid East are tucked away among the Soviet-style buildings in East Berlin.

A narrow passage next to a cafe leads to a courtyard exploding with murals, tags, and paste-ups.

A museum dedicated to the history of a terrifying secret police is now held in their former headquarters.

A sprawling Baroque park with 300-year-old hydro-pneumatic waterworks.

Started as a kitchen garden, now the second largest botanical garden in the world.

A tour of underground Berlin takes you through WWII air raid shelters and tunnels used to smuggle people out of East Germany.

A whimsical and twisted animatronic monster tour beneath the streets of Berlin.

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

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

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

This Croatian fairytale castle is slowly falling apart thanks to years of neglect.

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

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

A unique seaside cave where Aleister Crowley faked his own death.

The world's oldest bookshop still in operation.

This small chapel is built of human bones and decorated with a golden skeleton.

A 16th century chapel decorated with bones, skulls, and entire bodies hanging from the wall.

Houses are tucked between, on, and underneath giant boulders.

One of the most beautiful bookstores in the world hides a neo-Gothic interior behind an art nouveau facade.