One of Ireland's most infamous prisons for rebels including men, women and children.

Perfectly preserved ancient monastery in an impossibly dramatic location on a rocky island in the Atlantic.

This ancient Greek place of assembly and marketplace is being revealed layer by layer below the modern Athens cityscape.

Replicas of Apollo's leonine stone guard cats still line a sacred row in Greece.

This legendary city has been a tourist attraction for centuries.

A 2,000-year-old computer demonstrates remarkable engineering and astronomical precision.

A minotaur, a labyrinth, and a dubious restoration pull in visitors from around the world.

The hallucinogenic center of the ancient world.

Is this statue at Naumberg Cathedral the fairest of them all?

Art historians have debated the identity of this medieval stone rider since the 19th century.

The fairy tale castle of the "fairy-tale king."

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

These bronze pamphlets remember a remarkable group of Germans who fearlessly opposed the Nazis in the very center of their power.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

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

Beneath the impressive baroque cathedral that rises from the center of Berlin lies the largest collection of Prussian royals in the world.

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

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

The world's tallest church tower reveals a spectacular view to anyone up to the task of climbing the daunting staircase.

The largest crypt ever constructed in France was built in the 11th century on an ancient Druid sacred site.

The encased skull that is widely believed to belong to St. John the Baptist.

Science fiction's grandfather has a fittingly marvelous tomb.

A favorite Paris bar for U.S. expats, including Gershwin, Hemingway, and James Bond.

Old Danish castle immortalized in Shakespeare's Hamlet.