If you're visiting the City of Lights, right under your feet, you'll find the Paris Catacombs and the bones of over six million people.
Millions of people travel to Paris every year. With the Eiffel Tower and the Louvre, the city has some of the most recognizable landmarks and tourist attractions in the world.
However, few of them make the time to visit the city of light's dark corners: the Paris Catacombs.
Housing some of the largest ossuaries in the world, if you ever find yourself in Paris, make sure to visit the City of the Dead resting right beneath your feet.
So what is it? An ossuary is a site used as a final resting place for skeletal remains. Sometimes these can be just a box or a room or, as is the case with Paris, an entire underground lair. Down in the Paris Catacombs, you will find skulls and other bones from over six million people.
While it might sound like Paris was under the control of a killer cult for a couple of centuries, the reasons behind the ossuary's existence are quite practical. They ran out of room at cemeteries. Lack of space is a common problem for any city that sees rapid growth, which is exactly what happened to Paris in the 17th century.
Nowadays, population booms typically signify that it will be hard to find affordable housing or that traffic's going to be a nightmare. Back then, it meant that proper burials were growing harder and harder to come by. At the same time, Parisians were beginning to realize that placing cemeteries everywhere wasn't a great way to go about promoting public health.
Before they were the catacombs, these 13th-century tunnels were quarries for limestone. Over time, the resources were extracted, and so the tunnels were simply abandoned. The solution to use them as ossuaries became pretty obvious.
Beginning with the 18th century, the tunnels began functioning as underground cemeteries and, by the 19th century, they became a rather odd, but popular tourist attraction.
In the 1940s, when Nazi forces occupied Paris, French resistance members used the catacombs as hiding places to meet and plot against the invading enemy.
In modern times, artists have used the Paris Catacombs to display their own work, and even built a functioning movie theater in the underground cemetery. Counter-culture groups have also held concerts and parties throughout the catacombs, despite the illegality of doing so.
Nowadays, you can take a 45-minute tour of the catacombs. Of the 4.2 square miles of cemetery, guests can tour about 1.2 miles of it.
Tourists can also see the remains of many former prominent Parisians such as the painter Simon Vouet, the sculptor Francois Girardon, and the writers Jean de la Fontaine and Francois Rabelais.
The catacombs cover much of Paris's underground. If you're ever wandering through the city and would like to know if there is a giant bone cemetery underneath your feet (which is a question most thoughtful people would like to know the answer to), look around for tall and, more importantly, heavy buildings.
If you don't see many, the answer is likely "yes." One of the catacombs' main drawbacks is structural integrity. Since they can reach depths of 65 feet and are located directly under Paris, it makes it pretty hard to place tall buildings above them because they can't have a large foundation.
Next, learn about how thieves in Paris drilled through these same catacombs to steal $300,000 in wine. Then, check out these images from the Catacombs Nightclub of the 1940s, that tried to recreate the macabre environment of the Parisian tunnels in Columbus, Ohio.