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

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

Paris' linguistic guide to the international language of, yes, love.

The historic Masonic Lodge in which the first-ever female Mason was initiated.

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

The spiral staircase hidden inside this giant Parisian column was likely built for Catherine de Medici's astrologer.

One of the oldest masonic museums in Paris.

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

This life-size replica of the Statue of Liberty's flame is also a tribute to Princess Diana by default.

The headless bodies of more than 1,300 guillotined victims of the Reign of Terror are buried here in mass graves.

Remains of Roman amphitheater hidden in a sleepy quarter of Paris.

This former “ante-chamber to the guillotine” has been refurbished to illustrate the brutal history of French justice.

Stroll through retro Paris while shopping for old postcards and discarded doll heads.

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

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

The macabre collection of Jacques Sirgent, an expert scholar on the undead and all of their trappings.

This massive library holds what was once the largest book collection in the world.

The vast, legendary catacombs hold secrets much stranger than stacked bones.