
Underneath the streets of Paris lies a second city, a city of the dead. Known as the Catacombs of Paris, this twisting network of passages and chambers is stacked high with thousands upon thousands of human bones.
The estimated 186 miles of underground tunnels date from Roman times but stood empty for hundreds of years. However, by the end of the eighteenth century, the city's cemeteries had begun to overflow with rotting human remains. As the piles of bodies grew and disease began to spread, the Inspection générale des Carrières (or Inspector General of Quarries) decided along with Police Lieutenant General Alexandre Lenoir that the abandoned quarries should be used as an underground graveyard.
In some places the bones are laid in careful patterns. Leg bones are stacked high in rows topped by skulls staring blankly. In other chambers, however, fragments of legs, arms, ribs, and heads litter the floor. There are rooms where you must walk across a sea of skeletons in order to pass through. There is no way to tell how deep these piles go or how many layers of bones lie beneath your feet.