An odd museum dedicated to French fakes.

A museum which takes visitors to the côté obscure of Paris.

One of the world's most complex timepieces.

The world's largest reflecting pool is just two centimeters deep.

This ancient Roman bridge and aqueduct still stands as a wonder of classical construction.

This historic island prison holds one of the dungeons from the Count of Monte Cristo even though it is a work of fiction.

A Gothic cathedral created from volcanic rocks.

This massive blockhead sculpture hides an entire library.

The only remaining collection of flayed figures made by French "madman" Honoré Fragonard.

A Parisian cemetery where the elite and artistic are interred beneath an eccentric collection of tombs.

This French ghost town from World War II has been left as a memorial to German atrocities during World War II.

The oldest stone house in Paris was built by its most famous alchemist.

Thousands of exquisitely carved stone water storage wells, hundreds of stone steps fill this exquisite medieval stepwell.

The residents of this ominous-sounding street in Pennsylvania liked its name so much they fought to keep it.

Reverend Jen's unique museum/living room showcases her troll collection.

A DIY art gallery/music venue/lecture hall dedicated to video game culture.

A miniature rainforest is growing inside of a Midtown Manhattan office building.

A beautiful and abandoned New York subway station from 1904, complete with chandelier.

The Sun King's military models, saved from the Louvre.

A subterranean shelter remains intact under a busy Paris railway station.

The history of radiation is on safe display at the foot of a radiation science laboratory.

This Parisian fountain is a little bit fantasy and a little bit nightclub.

This abandoned subway station beneath the Waldorf-Astoria hotel is allegedly used to secretly transport presidents.

Hidden beneath the streets of London is a secret subway that only carried mail.