‘Behind the neat stacks of skulls, tibias, and femurs in the Paris catacombs lies a chaos of bones. In the 18th and 19th centuries the city dug up millions of skeletons from over-flowing cemeteries and poured them at night into old quarries.’
National Geographic, Paris Catacombs:
Paris has a deeper and stranger connection to its underground than almost any city, and that underground is one of the richest. The arteries and intestines of Paris, the hundreds of miles of tunnels that make up some of the oldest and densest subway and sewer networks in the world, are just the start of it. Under Paris there are spaces of all kinds: canals and reservoirs, crypts and bank vaults, wine cellars transformed into nightclubs and galleries. Most surprising of all are the carrières—the old limestone quarries that fan out in a deep and intricate web under many neighborhoods, mostly in the southern part of the metropolis.