The underground sanctuary of a mysterious ancient cult.

The middle finger of modernity.

The yawning maw of this pagan visage is said to bite off the hands of liars.

Rome's semi-secret peephole vista is also a former Crusader stronghold.

This hidden Art Nouveau courtyard is an opulent feast for the eyes.

This community on a small Venetian island has taken to painting their houses in bright neon hues.

A master of trompe-l'oeil creates a stunning, tourist-fooling dome out of a flat ceiling.

A 16th-century horror show built in a lovely Italian garden.

An alchemist's "magic door" stands in the middle of a Roman park.

Architectureal fantasy quarter of Rome.

This Venice bookstore has resigned itself to constant flooding by keeping its books in bathtubs and boats.

A submerged archeological park still holds the wonders of a Roman Sodom.

An Italian crevasse filled with abandoned buildings gives visitors a look at the world without humans.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

A train ride to the middle of nowhere gives its passengers some of the most iconic views of Japan's seasons.

A lesser-known sister to Paris's world-famous museum, located within a Buddhist sculpture paradise.

Japan's iconic sci-fi hero rendered to 8-bit by notorious French street artist Invader.

Walk through Czech history in Prague's largest graveyard.

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

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

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

Macabre astrological automaton clock dating to the late 1400s.

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

The history of occult science is turned into a creepshow at this lurid Prague tourist attraction.