This fortress was designed to prevent a Nazi invasion but was never used.

Tall columns of volcanic basalt make up this improbable-seeming rock formation.

The sanctuary holds what was once believed to be the saint's incorruptible tongue.

This Czech military museum is home to pink tank that was once a symbol of art and political rebellion.

The largest manmade caves in Europe now function as a motorbike club's headquarters.

The 14th-century ruins are said to contain healing powers.

The mystery of the Putim Ossuary involves a tricorn hat.

Mysterious painted skulls in Moravia.

Folklore says this medieval fortress was plopped atop a portal to hell to trap the demons below.

Enormous sandstone towers loom within a Czech forest.

The deepest sinkhole in Central Europe comes with a grisly tale and an unusual nickname: “The Stepmother Abyss.”

Bohemian paradise covered in majestic forests.

One man's personal collection of KGB memorabilia is presented along with his strange viewpoint.

Thirty creepy ghosts now inhabit this decaying 14th-century church.

Europe's largest natural bridge has a 19th century royal chateau built into its side.

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

This artificial cave looks like something out of a fairytale.

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.

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

Walk through Czech history in Prague's largest graveyard.

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

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