A small marionette collection located within the dark cellars of an 11th-century Austrian castle.

Soaring over 6,000 feet in the Bavarian Alps, this beer garden was once Hitler's 50th birthday present.

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

The beautiful, ornate weather station is the most popular geocache in Salzburg.

Created as a "model concentration camp" to hide Nazi atrocities from the international community, this former camp-ghetto now holds a museum and memorial honoring the lives lost within.

A controversial artwork draws attention to the dark history of Prague's "Suicide Bridge."

A collection of old neon signs from all over Poland line a secluded courtyard.

Underneath this small church are 15,000 bones, arranged by an obsessive academic.

An 18th century fountain and two columns are all that remains of Rome's forgotten river harbor.

This is the oldest Roman-made bridge in the city still existing in its original state.

The remains of this 2nd-century Roman temple are incorporated into a modern building.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

Museum dedicated to literary greats of the Romantic Period is also the home in which Keats met his untimely end.

Architectural monsters are devouring this palace's every door and window.

The crypt of the imposing Stephensdom holds royal intestines and thousands of skeletons.

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

When the rain falls, this drain system turns into a musical instrument.

One part local history, 99 parts gruesome haunted house.

The naturally mummified body of a peasant girl saint.

This bustling Italian plaza is built on the ruins of an ancient Roman amphitheater.

Fortified medieval tower house with lovely roof garden.

The world's most active stratovolcano is almost always erupting.

This former quarry is now a picturesque gorge that hides a sunken lake.

A saintly relic hidden in a Prague church basement.