This Hungarian castle was built out of cardboard and wood until it proved so popular that it got upgraded to stone.

A 19th century artistocrat's mansion, turned into a library, hidden in a modern library.

This Budapest bar allows drinkers to leave their mark on the walls, floor, and even ceiling.

Visitors flock to the historic birthplace of radiobalneology for its therapeutic radium treatments.

Before serving as James Bond's Casino Royale, this Victorian-era spa catered to the world's elite.

An enormous and lavish Gothic church in Czechia.

Unique house covered in a nightmarish mural of demons, ghosts and monsters.

Underneath the city that invented pilsners are a series of historic tunnels that have been storing beer for centuries.

A former squatter's paradise outside Prague.

This network of conjoined cellars was riddled with traps and supposedly allowed the townspeople to pretend their homes were deserted.

The soulless eyes of 82 bronze children stare on forever in remembrance of a horrifying World War II massacre.

These 17th-century mummies are no longer naturally preserved, but remain on display today.

A crucified and bearded female saint.

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

This bar and museum are devoted to the controversial comic book work of Kája Saudek.

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

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

Mummified monks and the accidentally interred, in a 17th-century crypt.

A spiral staircase twists to the top of this unusual Czech lookout tower.

The world's greatest slide descends 18 stories from this looping mountaintop viewing platform.

Bohemian paradise covered in majestic forests.

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

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

Two monstrous faces loom over a village in Czechia.