This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

France's most famous cemetery, with some of its most curious tombs.

A statue in Budapest's Liberty Square honors the former U.S. president's efforts to end the Cold War.

An existential riddle in the world's largest ancient castle.

Synagogue built from the stones of Solomon's temple contains the golem of Prague.

This tipsy office building in downtown Prague was originally called “Fred and Ginger.”

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.

This sprawling concrete suburb of Kraków was designed by the Soviet Union as the model proletarian city.

In the midst of a living monument to Soviet social engineering, Polish Catholics built this church by hand.

Poland's oldest surviving university building holds a wealth of historic science instruments including some used by Copernicus.

St. Mary's features one of the most spectacularly decorated cathedral interiors in all of Europe.

Real bones which are said to have belonged to a Polish dragon.

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

An underground city of salt.

An imperial church bombed to ruins during WWII now stands as a jagged memorial.

A monument to the three wars that led to German unification towers within a Berlin traffic circle.

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

The birthplace of Karl Marx is now a museum dedicated to the communist revolutionary's life and work.

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

This Dresden church was purposely rebuilt Protestant after being demolished in World War II.

The "Prussian Versailles" that is as glorious today as when it was built.

The largest treasure hoard in Europe is contained in a castle that was bombed out during World War II.

Dress up like a miner and take a slide into the disco-lit depths of this once foundational salt mine.