The Catacombs are located in Montparnasse in the 14th arrondissement
A French instructor once told us that during the French Revolution and the Reign of Terror when the guillotine was very active, they created the catacombs to store all the bodies.
Our understanding is that Paris was overrun with sprawling cemeteries which often caused health problems. It was a large project to escavate the bones and arrange them in the quarries. These were gypsum and lime quarries (gypsum is an ingredient of Plaster of Paris) The bones are artfully arranged and organized according to the cemeteries which was the source of the bones. The Holy Innoscents Cemetery was the oldest and largest cemetery, now marked by the Fontaine des Innocents
New York Times
Catacombes (Letter of Recommendation)
The Secret Is Out on a Cherished Underground Haven Paris Journal)
Beneath Paris’ City Streets, There’s an Empire of Death Waiting for Tourists
This Halloween, Who Wants to Spend a Night in the Paris Catacombs?
Le Diable Vert a graphic novel set in and under Paris during the Nazi occupation, it combines history—Resistance fighters hid in the tunnels—with folktales of a subterranean green devil.
When we think of Catacombs, we think of Paris
But did you know New York and Boston also have Catacombs?
National Geographic (requires a NG account)