The Underground of Paris is a shadow of the City of Light itself, which is just as vast and less well known. The most well-known Paris Metro and the Paris Catacombs only form part of the Parisian underground world. The expression “Underground Paris” (or sometimes Les Dessous de Paris ) included the elements of the Parisian underground: quarries, catacombs, basements of buildings, sewers, technical galleries and underground routes (metro and RER, road tunnels). It also includes the organisms and ecosystem that live here, including mushroom farms, as well as the Aboriginal: rats, bugs, and microbes.
Paris is a tale of two cities. There is the City of Light, above ground, with its beloved Eiffel Tower or the Louvre Museum. But there is also a Paris underground city, the invisible city beneath paris, lesser-known by visitors and locals. There are at least 130 kilometers of Paris underground tunnels and secret places, a network of galleries, rooms, and chambers… and it is possible to explore some of them through exciting Paris underground tours. Most of these tours are also a great way to learn lesser-known parts of the history of Paris.
Paris is a thousand-year-old settlement, so there are plenty of reasons to explain the origins of the Paris underground world. Due to the geological formation, there are some natural tunnels, some of which have left medieval paintings or graffiti. The earliest human intervention in the underground world, including the foundations of more and more large buildings, and the tunnels left behind by the mines, some of which later became the Paris Catacombs. Later, when Paris was already a city with a huge population, the digging of sewers was a matter of course. Finally, the Paris metro system once again enriches the underground world.
The invisible city was the realm out by the upper city has been hewn and drawn, block by block over centuries. This invisible city follows different laws of planning to its surface counterpart. Its tunnelled streets often kink and wriggle, or run to dead ends. At junctions, three or four tunnel-streets might extend out. There are slender ways running from southwest to northeast of the city. There are inexplicably broken grids of streets, or hubs where the spokes of different tunnels meet. Coming off some of the tunnels are chambers, irregular in their outlines and with dozens of small connecting rooms.
Through the Phantom of the Opera, many learned of the existence of the mysterious lake under the Opéra Garnier. Under the Printemps Haussmann also runs an underground river called the Grange Batelière. The sewers of Paris, the archaeological crypt under Notre-Dame or the Catacombs of Paris reveal to you what is hidden under the bowels of the capital.
The Paris metro system is a delightful experience that takes passengers to their desired destination quickly, avoiding the terrible traffic conditions on the ground in Paris. If you are used to taking the Paris metro, then you have probably noticed these disused stations that your train crosses without ever stopping there. These are called ghost stations. In total, there are 16. Some have been closed or moved, others have never been opened.
Sometimes these are well- kept secrets, sometimes not. Under the Parisian monuments hide new places and prohibited to the public. Unknown are also the Parisian bunkers. And yet, under the Gare de l’Est and the Hôtel-Dieu each have one. Under the Paris Mint is also an air-raid shelter. Even under the Champs de Mars is what is nicknamed the Eiffel Tower bunker.
Types
The underground world of Paris is mainly composed of the following elements:
Quarries
These old exploitations, most often medieval (for example of resistant limestone from the columns of Notre-Dame cathedral, gypsum north of the Seine, of coarse limestone in the south) or from the modern era can be immense as under the Montmartre hillock or well at Parc Montsouris. They are the cause of many sinkholes, cracks or landslides of buildings on the surface since the large-scale urbanization initiated in the 17th century.
Catacombs
Originally, simple galleries linking the quarries together, they were individualized to serve as warehouses (civil and military) and especially as an ossuary at the old cemetery of the Innocents. They played a role during the liberation of Paris by allowing Colonel Henri-Rol Tanguy to hide in a shelter connected to it. Today, a small part of them has been transformed into a museum. Open to the public, it is very visited, especially by foreign tourists. The official entrance at Place Denfert-Rochereau only gives access to the “legal” part of the network, but some, the cataphiles, know of other much less official entrances.
Basements of buildings and underground parking lots
Many buildings in Paris have basements as storage spaces, the most well-known being the basements of department stores and the underground wine cellars of well-known taverns. The underground parking lots, private or public, include several tens of thousands of individual spaces; they are subject to very strict regulations. Some old buildings or war shelters can be accessed through the underground network.
Sewers
Nearly 2,600 kilometers long, the sewers of Paris constitute all the underground conduits intended to collect and evacuate runoff water resulting mainly from the rains as well as the waste water produced by the various human activities on the territory of the city of Paris. Used to be described in literature as a dark and nauseating place, for example, in the episode of Les Misérables where Jean Valjean saves Marius by carrying him on his shoulders inside the sewers.
The sewers of Paris have evolved considerably since the work undertaken by the prefect Haussmann and the engineer Eugène Belgrand, both at the origin of the contemporary network. Under their leadership, all the streets of the capital were in fact lined with an underground gallery, making Paris one of the most modern cities in the world in this respect.
Technical galleries
A technical gallery is an underground gallery, usually concreted, containing cables, conduits or pipes supplying buildings and urban structures. Often linked or associated with the previous ones, these are various pipes carrying water, gas, electricity, district heating, telephone and cyber cables, tires, etc. Large enough to allow several people to circulate there, it is an urban infrastructure, usually located between 5 and 10 meters deep, although some can be much deeper.
Over the course of the 20th century, suburban infrastructures (metro, sewers, car parks, etc.) have multiplied, which de facto reduces the possible space for new technical galleries. For this reason, the construction of these galleries has been in decline since the 1980s, and the current electricity or telephone cables are more often placed in large pipes which replace the old galleries. The heat network, however, still requires relatively wide tunnels, easily accessible by technicians. Most large cities have a complex network of technical galleries, connected to the underground buildings.
Underground ways
Metros and RER, for example tunnels or underpasses of the Paris Metro or the old or modern rail network.
Underground road
In modern times, underground roads and underground shopping malls are becoming more and more common. Initiated on the boulevards of the Maréchaux then in the district of Les Halles, given the increasing density of traffic, it tends to take more and more importance.
Channeled waterway
After entering the vicinity of Place de la Bastille, the Saint-Martin canal becomes an underground river, and this closed space can be experienced on a guided tour of the canal.
Main Attractions
The undergrounds of the capital which hold many surprises. Catacombs, ghost stations and secret lakes, Between the mysterious catacombs, the intriguing ghost stations, the secret bunkers and the underground lakes, a whole strange and timeless world is developing in the bowels of Paris.
The Quarries of the Capuchins
The mines of Paris comprise a number of abandoned, subterranean mines under Paris, France, connected together by galleries. Three main networks exist; the largest, known as the grand réseau sud (“large south network”), lies under the 5th, 6th, 14th and 15th arrondissements, a second under the 13th arrondissement, and a third under the 16th, though other minor networks are found under the 12th, 14th and 16th for instance. The commercial product was Lutetian limestone for use as a building material, as well as gypsum for use in “plaster of Paris”.
Just below the Cochin hospital, located in the 14th arrondissement, hide old underground limestone quarries that were exploited between the 12th and 17th centuries. About twenty meters below the surface, it is now possible to visit them in small groups (by reservation) by taking a staircase, precisely made up of 102 steps. Managed by the SEADACC association, the Carrières des Capucins are revealed to visitors like a museum, through labyrinthine galleries stretching over 1200 meters in length.
The catacombs of Paris
The Catacombs of Paris are underground ossuaries in Paris, France, which hold the remains of more than six million people in a small part of a tunnel network built to consolidate Paris’ ancient stone quarries. Extending south from the Gate of Hell, this ossuary was created as part of the effort to eliminate the city’s overflowing cemeteries. From 1786, they were used to store the bones of 6 million peoplefollowing the closure of many churches and the exhumation of bodies from cemeteries.
A small part of this gigantic ossuary can be visited, very close to Denfert-Rochereau, about 20 meters underground. It was opened to public visitation from 1874. The ossuary became a novelty-place for concerts and other private events in the early 19th century. Since 2013, the Catacombs number among the fourteen City of Paris Museums managed by Paris Musées.
The Montsouris reservoir
This reservoir, also called the Vanne reservoir (because it stores, among other things, water from the Vanne river in Aube), is one of the 5 main water reservoirs in Paris, which can accommodate nearly 300,000m3 of water. It was built between 1868 and 1873 to supply water to the entire southern part of the city, in a context of weakening local sources of drinking water.
The Gare de l’Est bunker
Under tracks 3 and 4 of the Gare de l’Est, there is still a mysterious bunker dating from the Second World War. This underground niche was used to manage the departure of trains from the station and ensured secret communication with the other stations in the city. It was also designed to protect the population from possible gas attacks that Paris had already suffered during the First World War. Today, the bunker, owned by the SNCF, is still intact, but very rarely opens its doors to visitors.
The reservoir of the Opéra Garnier
Under the stage of the Opera, a small staircase leads to a strange water reservoir which, since its creation in 1861, has fueled the most absurd rumors in the capital. Its construction served to contain underground infiltrations and thus constituted a real advantage for the Palais Garnier. In particular, it gave firefighters the possibility of controlling fires more quickly and efficiently. Much mystery surrounds the presence of this vast basin of water accessible by boat to such an extent that the legend relating to the presumed existence of a lake.
The Paris Sewer Museum
In Paris, the sewers are one of the capital’s tourist attractions. A network that is made accessible to visitors over nearly 2400 km and allows you to learn more about wastewater management and thus measure the importance of sewers in the city. A particularly instructive visit to the bowels of the city to discover the largest and most modern sewer network in the world. This ” sewer museum ” welcomes nearly 95,000 visitors a year. The route provides information on the history and operation of the Parisian sewer network. The museum can be visited: access is open to the public on the left bank of the Seine, at the foot of the Alma bridge.
The Lhomond shelter
Just below the building at 70, rue Lhomond in the 5th arrondissement. Designed to accommodate a maximum of 1,700 people, this shelter was accessible via 3 access doors: a main staircase and two emergency exits, indicated by inscriptions painted in black. It was intended to protect, in priority, the children of the schools of the district who took refuge there especially between 1943 and 1944.
The cathedrals of La Défense
Under the tall buildings of the bubbling district of La Défense, hide real underground “cathedrals”. Built to accommodate the metro station which ultimately did not see the light of day, these large empty spaces, with a colossal ceiling height, are today abandoned. Yet with some work, these cathedrals could largely be refurbished and reused for useful purposes.
Mushroom farm
There used to be a large number of mushroom farms underground in Paris, until the middle of the 20th century, the majority of mushroom houses were made in former underground quarries. Market gardeners who stored their vegetables in quarries were quick to take advantage of the natural properties of quarries: high humidity, cool temperatures and constant, regulation of air circulation relatively easy. The development of quarries for growing mushrooms is relatively simple: installation of plasterboard partitions, stone walls or more simply plastic sheets to segment the quarry into culture chambers, possible installation of radiators and water inlets; ventilation by the old ventilation shafts.
They flourished in careers from the 19th century to the middle of the 20th century. At the end of the 19th century, there were more than 250 producers in the Paris region. In France, the majority of quarry mushroom houses disappeared in the 1970s – 1990s due to competition from Eastern and Asian countries, which cultivate mushrooms in refrigerated sheds, with much cheaper labour. French producers also use refrigerated sheds and rare are those who continue to cultivate the mushroom in quarries. Some mushroom farm reserving it for its more expensive prices to a high-end audience.
Underground ecosystem
Paris Underground is also with an ecosystem of its own, with underground world hosting various species. Urban explorers should be extremely cautious exploring the undergrounds, the great amount of them are uninhabited and/or flooded, and wildlife is not rare there. Rats, cockroaches, woodlice and even cicadas have taken over the place to live in symbiosis with us. They eat our waste, invade our cellars, nibble our electrical wires. Pests, but also partners who clean and maintain a certain cleanliness in the capital. Indeed, without the rats, the sewers would certainly be clogged.