A dreamlike medieval church dug into the tuff rock, with unusual carvings and possible traces of the Templar knights.

A lavish 16th-century mansion filled with spectacular staircases, fantastic frescoes, and gorgeous gardens.

Ride a boat through this magnificent underground world, which now doubles as a theater.

This breathtaking monastery was established by Saint Benedict himself 1,500 years ago.

This military mausoleum captures the solemn grandeur that most memorials only aspire to.

A gorgeous medieval library where the books are kept in chains.

Crumbling ruins of the thermal baths that once attracted royals and aristocrats from throughout Europe.

The world's oldest surviving anatomical theater, where "the dead are pleased to help the living."

A formerly opulent Italian village is now a crumbling ghost town that no one really knows what to do with.

A once-luxurious, now abandoned hotel in the Italian Alps.

The skulls and bones of thousands of soldiers line the walls of this small Italian chapel.

Long-abandoned art nouveau baths beneath Milan's Piazza Oberdan.

The sinister ruins of one of the worst dam failures of the 20th century lie in this astonishing alpine setting.

An ancient artistic garden parlor full of hidden water wonders.

Gigantic mosaic sculptures of the figures on Tarot cards fill this colorful Tuscan garden.

This abandoned Brutalist treehouse is a hidden architectural relic.

Where Aleister Crowley taught magick in "La Chambre Des Cauchemars," his "Chamber of Nightmares."

This real life asylum of horrors is now an abandoned ruin that hides the unbreakable code to one patient's insanity.

One of the world’s smallest bars, just 13 square feet, is brimming with speakeasy flair.

A Milanese café entirely designed by the American director Wes Anderson.

Eco-village hidden in the foothills of the Alps that created a massive system of psychedelic underground temples.

Crushed coral and crystals give the sand its signature coloration.

Filled with goldfish swimming in a shallow pool of sea water, this ancient crypt is more wishing well than burial site.

Abandoned medieval hill town.