A castle from the Holy Roman Empire that hosts traveling youth... in its stables.

This abandoned coliseum was intended to be a grand Nazi rallying ground before it was halted at the end of the war.

Among the ostentatious rococo ornamentation of this church, an image of death cuts the life-thread.

The patron saint of spinsters grasps a container of dried blood.

Golden cobblestones remember a time when this small alley was used to avoid having to give a Nazi salute.

A small square plaque marks a failed assassination attempt that could have changed history.

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

The footprint of a frustrated devil in Munich's Cathedral.

When a medieval fire claimed the original St. Stephen’s Cathedral, it sparked a pattern of unquenchable organ building.

A 19th-century artistocrat's mansion, turned into a library, hidden in a modern library.

The most visited, and possibly most controversial, museum in Germany.

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

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.

A pair of connected skyscrapers form this symbolic gateway.

Destroyed Serbian army headquarters sits half crumbled in a largely revitalized Belgrade.

A towering spire in the fortress of Kalemegdan honors the victorious armies of Serbia during their struggles against the Ottoman Empire.

Bizarrely shaped rock formations in northwest Bulgaria come with equally bizarre legends.

The second-largest Jewish temple in Bulgaria was deserted after World War II, seized by the communist government and then abandoned again.

A Roman monument to their own civil engineering prowess.

A giant portrait of an ancient king looms over the river.

This 14th century castle withstood years of battle but is now sliding off the hills into the Danube.

The massive, original Colgate Clock is mounted on a defunct factory building that was once a prison.

A turn-of-the-century architectural marvel built on healing mineral springs and salt licks.

Known as the "Cross At The Crossroads," this massive metal cross is just short enough to avoid the FAA.