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

The recovered bones of martyrs slaughtered during The Terror are on display in this church crypt.

Where the high court feasted, frolicked, and high courtesans put their royal lovers' diamonds to the test.

This banal Parisian entranceway is not what it seems.

Pitié-Salpêtrière was the dumping grounds for women who received the dreaded diagnosis of "hysterical."

A modern-day Lascaux cave underneath Paris.

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

The narrowest street in Paris.

The curious underground history of keeping Paris clean.

Twelve grave-faced marble angels guard the emperor's tomb at Les Invalides.

How did a French journalist’s grave become the sexiest statue in the cemetery?

A unrivaled and rather horrifying collection of wax dermatological models.

A grotto-like lodge decorated with gilded mosaics, rocks and a noisy waterfall was the setting for the most sumptuous pleasure house of 1900s Europe.

In the best of all possible worlds, everyone will get a chance to see this statue in which Voltaire's heart is interred.

A majestic lion statue guards this Parisian botanical garden, and feeds on an unsettling item.

The subterranean "lake" below the Paris opera house inspired the Phantom of the Opera's lair.

Statue of death tucked in the University of Medicine courtyard.

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

The water-powered carriages are long gone, but for over a century this funicular railway has been the fastest route to the highest point in Paris.

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

Exquisite wall sculptures carved in secret by an early quarryman in an obscure corner of the Paris Catacombs.

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

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

A mechanized clock where a man fights off a dragon, crab, and rooster.