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

This walkway is so narrow it needs its own light to stop pedestrian traffic jams.

What looks like a crashed Zeppelin is actually a bright, airy reading room perched atop a modern museum.

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

Street artists transformed an abandoned air vent into the beloved Star Wars robot.

What looks like a suicide in progress is actually a statue of Sigmund Freud.

The risqué mixed-media sculptures are supposedly a metaphor for Czech politics.

The first museum in the world devoted to sexual gadgetry.

Walk through Czech history in Prague's largest graveyard.

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

A steampunk-styled three-floor factory churning out art, activism, and electronic beats.

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

Countless grotesque faces stare out from this eerie Prague art wall.

Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.

Two stunning 17th-century libraries and a cabinet of curiosities.

A church of bones, decorated with 40,000 human skeletons.

A marvel of technology a century ago, this disused power station now offers a lovely glimpse into the industrial design of the past.

The abandoned "Red Star Train Graveyard" is the final rusting place for precious artifacts of train history.

The remains of a 13th-century Romanesque church lie abandoned on a hillside.

World's tallest cigar-shaped radio tower.

Outside of Budapest, a reconstruction of a 16th-century fortress.

A stunning Art Nouveau cinema in the heart of Budapest.

This castle was designed to have as many windows as there are days in the year.

The ruins of an early 1900s neo-Baroque mansion sit nestled in a local park in the Hungarian plains.