Origins of the Catacombs
Dug by the Romans and expanded later by the French, the tunnels beneath Paris supplied limestone to the city. By the 18th century, they were becoming unstable. Officials shut the tunnels down in 1776. A collapse of one of the tunnels destroyed an entire street.

Les Innocents Cemetery
At the same time, the city had another problem: it’s graveyards were full. By 1763, burial within city limits was illegal. However, that didn’t fix the cemeteries that were already overflowing. Les Innocents became a particular issue in 1780. Extreme rain that year caused one of the cemetery walls to collapse, and bodies tumbled into the street. Louis XVI shut down the graveyard permanently. Before that, it had been a burial site for ten centuries.
With two major problems in the city, officials decided to solve both at once. The bones from Les Innocents and other cemeteries were dug up and dumped into the tunnels.
Working at night, workers moved the skeletal remains of seven million people beneath the city. Some bones were over twelve hundred years old.

Map of the Catacombs
Louis-Héricart de Thury
Thury took it upon himself to renovate the tunnels beneath Paris. He rearranged the bones that had been dumped into the tunnels and added some of the decorations from ground-level graveyards in the city. He made intricate patterns from the different bones in a variety of styles, back-filling the space behind his designs with more bones. His arrangements provided more support to the tunnels.

Bone Designs
The tunnels were completely off limits to the public. However, after the creation of the mausoleum in 1809, authorities permitted some tours. These underground excursions weren’t open to the public, they were an exclusive experience for the elite. About four trips visited the catacombs each year. Today, the catacombs are open to all, and have become a major tourist attraction.
Mystery of Les Guillotinés
Historical accounts tell us that the victims of the guillotine during the French Revolution came to rest in the catacombs. Architects of the Reign of Terror, such as Maximilien de Robespierre, lay beside their aristocratic victims. However, a recent discovery has put that story into question.

Maximilien de Robespierre
Four cemeteries, among them Old Madeleine cemetery, were built for les guillotinés (victims of the guillotine). Old Madeleine was officially closed in 1794, because, like the rest of the cemeteries, it was full. This is when it was believed that les guillotinés were moved to the catacombs. Later, the Chapelle Expiatoire was built on the site of Old Madeleine to honor Louis XVI and Marie Antoinette. However, Louis XVIII had them re-interred at the Saint-Denis Basilica, the traditional resting place of French Royalty.