There's a lot of catacombs around the world, but the Paris Catacombs are well-known by travelers around the world. Only a little less than two-mile is actually open to the public, while the rest of the catacombs go on for over two-hundred-miles in an underground system of pathways and tunnels. The parts of the Paris Catacombs which are accessible to the public remain manicured, curated, and easy to navigate. A little less than two miles are marked with helpful signs that are visited frequently by tourists every day.The public access site is visited by locals and is one of the famous landmarks in Paris visited by celebrities.

Meanwhile, the illegal parts of the Paris' underground tunnel have been left as is, which are unmarked and potentially dangerous. Some locals are able to enter the catacombs via secret entrances around Paris, which are considered prohibited. Due to the potential danger of these passages, people are discouraged from venturing into Paris' underground tunnels.

However, despite the dangers, the urban legends, and the myths, there will always people who break the rules to explore the catacombs in their own way. These trespassing explorers have managed to reveal the secret parts of the catacombs through photos and videos they take. They've even mapped or memorized hundreds of entry points, shared tips by word of mouth, or provided visual tips to look out for while walking through the forbidden parts of the catacombs many creepy mazes.

Updated by Alex Renee on December 27, 2021: The Catacombs of Paris are a popular topic for tourists who love adventure, history, and a good ghost story! Many travelers have heard about venturing into the Catacombs' unknown, which can be a dangerous and illegal endeavor. We do not encourage travelers to engage in risky and dangerous behaviour; however, we updated the list to provide relevant links to additional resources and reading. We also added an entry about cataphiles, which are experienced urban explorers who love exploring the unknowns of the Paris Catacombs.

12 Some Parts Of It Are Open To The Public, But The Rest Is Off Limits

Approximately 1.5 kilometers of the Paris Catacombs are open to the public by the French authorities. However, once a person catches a glimpse of what the ruins look like beyond the maintained walking paths, there's no going back. Currently, Les Catacombs De Paris offers tours of the creepy maze that run a little less than a mile long, which leaves almost two hundred miles left un-groomed and off-limits tunnel systems inside the maze. Local rule breakers craving adventure have ventured into these prohibited tunnels.

11 Cataphiles Know Their Way Around The Catacombs

Akin to a secret society, the cataphiles are explorers that illegally venture into the secret passages of the Paris Catacombs. Cataphiles are said to know their way around catacombs and are a tight-knit community. In fact, these urban explorers rarely reveal their secret entrances to the catacombs, especially to tourists and outsiders.

10 Some Spots Will Require Maneuvering Since The Ceilings Are Low

Like many intricate mazes, the maze system in the Paris Catacombs is unpredictable due to narrow passageways and tight tunnels. Not only would it be dangerous to go in without a light, but it would also be dang near impossible to go in very far without causing serious injury. Eventually, someone might kit their head on a boulder or rock, knocking them unconscious. This is a big reason why the caves shouldn't be explored alone.

9 The Sheer Magnitude Of Length And Depth Can be Frightening

The Paris Catacombs, otherwise known as "The Empire of Death," are essentially one giant underground burial system to help with the overflow of dead bodies over-crowding the cemeteries of Paris. The city needed a place to lay to rest the remains of over six million people. This would require the Catacombs of Paris to be exceptionally deep and long. The cave goes on for miles and had been used for over 300 hundred years.

8 It's So Deep Underground There's Little To No Noise Pollution

Since adventure seekers often travel the Paris Catacombs for miles, some of them find empty passageways to rest and recharge. These hollow rooms, which are being used as resting points in the cave remain quiet and undisturbed, don't exactly get cell service. So far underground not even the sounds of the trains can be heard. Secret parties and meetings have been hosted inside the spooky underground tunnels of Paris!

7 Finding Entry Points Is Half The Adventure Or Just The Beginning

There are many words of mouth entry points into the Paris Catacombs, which have now suddenly made their way into online maps and forums. For years, people have shared theses same access points with their friends and families, which has increased illegal foot traffic inside the uncharted paths of the underground tomb. Perhaps eventually these points will be made accessible, but for now, many of them require a little hunting.

6 It's Less Scary In Large Groups With Provisions

Traveling deep down inside the Paris Catacombs will require an explorer to take certain precautions. Practical items like sturdy boots, muted clothing, food, and ID are useful for adventurers exploring the catacombs. Headlamps, water, and a first aid kit may also be necessary. When people travel in large groups they can share the responsibility of bringing these much-needed things. Plus, if someone gets hurt, they can collectively create a plan for getting help.

Related: 10 Creepy Things You Didn't Know About The Paris Catacombs

Many people have traveled through the Paris Catacombs for years. Some of these people have left their mark in various artworks or graffiti on the walls. Not only are the Catacombs well hidden from the authorities, but then some of the graffiti is meant to help navigate the various tunnels of the tomb, or share personal messages. The paintings also seem to add a bit more color and curiosity to the otherwise terrifying darkness.

4 It's Common To Cross Paths With Strangers And Other Groups Of Explorers

The actual designated parts of the Paris Catacombs that are intended for tourists have a maximum capacity for about 200 visitors at a time within the one mile curated space. However, the underground tunnels are so large and there are so many different tunnels, pathways, entries, and exits, that it isn't surprising to see small traffic jams or crowd of people waiting in hallways to turn into a joining tunnel.

RELATED: 25 Things In Underground Cities That Have Yet To Be Explained

3 It's Super Dangerous And Risky For The Solo Explorer

Nothing seems like it could be worse than getting trapped inside a narrow passageway hundreds of feet underground, but it has happened. The Paris Catacombs are not safe to explore for the solo traveler. There have been instances of people getting lost inside the underground tunnels. That's why it would be best to go with someone who can get help in case something bad happens, or just don't go at all.

2 It's Not Just Damp; Some Places Require Explorers To Walk Through Water

Since some parts of the Catacombs are exposed to natural cracks in the rocks and underground water systems, it can flood with waist-deep water. There have even been some photos of rooms with tunnels that have turned into full wells. These dark wet rooms require explorers to walk through water to get into the next chambers. Some people turn back at these points, but many rule breakers have continued onward into the dark.

RELATED: 25 Unearthed Places That Should Have Stayed Underground

1 For What Its Worth, The Official Entrance To The Catacombs Is Perfectly Fine

Once a guest pays the fee to visit the official Catacombs of Paris, they will quickly discover that the site is a whole lot of the same. The tour which lasts about an hour-long is not only enough time, but the clear paths, view of the illuminated water wells, and carved signs in the stone archways make it well worth the visit, and much safer than breaking the laws to travel into the complex cave system.

NEXT: 20 Places To Visit In Paris (That Aren't The Eiffel Tower)