This artificial cave looks like something out of a fairytale.

A 400-year-old mummified arm dangles from the ceiling of St. James the Greater, serving as a warning to thieves.

An eerie, existential museum dedicated to the author of "The Metamorphosis."

This doorless 20th-century elevator doesn't stop or slow down.

The tunnel's elegant proportions keep you snug with no claustrophobia freak-out.

This Prague museum collects brutalist relics and memories from the country's former Soviet rule.

A collection of anatomical samples from one of the first anthropologists to suggest that humans reached North America by crossing the Bering Strait.

Buried five stories underground, this Soviet bunker is packed with gas masks and Cold War paraphernalia.

Walk through Czech history in Prague's largest graveyard.

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

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

A museum of alchemy and a basement laboratory all housed in an ancient building in a Gothic tower.

An enormous and lavish Gothic church in Czechia.

Radical Bookstore and Community Space.

One of the best collections of wax anatomical models in the world.

The house that took a plunge into the facade of a museum.

A gift from Emperor Franz Joseph I to his wife.

A history of heat is on display at this unique Austrian museum.

This grand manse has been transformed into a museum devoted to one of the founders of Fantastic Realism.

On a winding Vienna side street, one museum has turned their windows into a monument to history’s peace-minded heroes.

Inside the corridors of this flea market, visitors are sure to find some obscure and odd treasures.

This series of Baroque passageways in Vienna's cultural center mix old architecture with modern art.

The solemn exterior conceals an opulent interior of this 17th century church.

A rooftop restaurant hides in plain sight atop Vienna's Palace of Justice.