Terrifying footage captured from the depths of the Paris catacombs remains a chilling unsolved mystery.

Now, there are some places where you might quite like to get lost. Maybe a forest full of puppies, or a palace inhabited solely by the best chefs in the world who want nothing more than to show you their latest recipes.

However, definitely NOT on the list of places you'd want to get lost is the Paris Catacombs. Even to visit them would be pretty unnerving, all while knowing you had a definite way out and a guide.

But what are the Paris Catacombs?

Well, imagine miles and miles of tunnels running directly underneath the city of Paris. They're dark, winding, and mysterious.

Oh, and they're also filled with hundreds of thousands of human bodies.

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Because people are nothing if not downright strange, some decided it would be a great idea to spend their time exploring the catacombs.

Among them is one unidentified explorer who once took a camera down with them to see what they could capture down there.

No-one knows who this person was, or why and when they made the trip into the catacombs. There are people who make it their hobby for some reason, but who this person was remains to be unknown.

Not only that, but no-one knows what happened to them either. It's a mystery wrapped in a mystery. All we have is the footage - which is, quite frankly, chilling.

The person's footage shows them exploring the hallow chambers of the catacombs, with them even picking up remains of a skull at one point.

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However, something spooks them enough to send them running for their life, with them dropping their camera and dashing off into the distance - presumably even further into the catacombs.

Nobody was ever reported as missing who fitted their profile, and it still remains a mystery today as to what happened to these presumed poor soul.

Despite many people exploring them only one person has been confirmed to have died in the catacombs. This was the unfortunate Philibert Aspairt, who died in 1793.

His body was found just 10ft from an exit, with an empty liquor bottle. To be fair, you'd need it.

But why do the Paris Catacombs exist? Well, their history is about as grisly as you might expect given their macabre contents.

In the late 18th century, Paris had a bit of a problem with how to bury its dead. The cemeteries were not only full, but overflowing. Literally.

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When there were particularly heavy rains the festering corpses of the recently, and perhaps not so recently, deceased would sometimes be washed from their graves.

As a result, the cemeteries in Paris were ultimately closed down.

But what to with all the bodies that were in them? Well, helpfully there were a load of abandoned mines which were situated underneath the city. These dated all the way back to the Roman period, when the city was first beginning to emerge.

In 15 months starting in 1786 millions of bodies were relocated from cemeteries into the catacombs, where they remain to this day.

So we have hundreds of miles of tunnels, filled with millions of bodies which could date back hundreds of years. If that's not the start of a horror movie I don't know what is.