Similar to Toronto, Montreal boasts an extensive Underground City. It is called "RÉSO" but is commonly just called "Underground City" or "La Ville Souterraine" in French. Located in the heart of Montreal's central business district, it is a series of interconnected buildings like office towers, shopping centers, hotels, convention halls, universities, and more.

But the famous Montreal is not the only maze running underground. More ice age era cave systems are being discovered. For those who would like to see some truly impressive caves, visit the Mammoth Caves National Park in Kentucky and see a whole alien world.


Montreal's Underground City

Toronto boasts a similar subterranean world - although in Toronto it is more of a tunnel system while in Montreal it is more of a massive shopping center with many tunnels.

While most of the system is made up of connecting tunnels underground. Some of the key passageways are located at ground level (there is also a sky bridge). Some describe it more as a subterranean city than a tunnel system. There are large commercial sectors in Montreal that are located entirely underground.

  • Usage: Over 500,000 People Daily

Canada is famous (or infamous) for its long and cold winters, during these times it is particularly useful. During these long and cold times, the Underground City is used by well over half a million people daily.

The Underground City is well-lit and is mostly climate-controlled. The combined length of the system is 32 Kilometers or 20 miles spread out over 12 sq kilometers or 4.6 sq miles. These are over 120 exterior access points to the network.

  • Length: 32 Kilometers or 20 Miles
  • Area: 12 Sq Kilometers or 4.6 Sq Miles

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In addition, some of the largest institutions in Montreal have their own tunnel networks that are separated from the Underground City (like Montreal Museum of Fine Art, Concordia University, McGill University, and Universite de Montreal.

The Underground City is being promoted as a tourist attraction by various Montreal travel guidebooks as well as Montreal's website. it is considered a remarkable urban planning achievement and is something that is well worth seeing. For most residents of Montreal, it is considered more of a large mall complex that links Metro stations.

After operating hours of the Montreal Metro (5:30 am to 1 am) some parts of the Underground City are closed.

  • Closes: Parts Close When The Montreal Metro Closes

It is considered to be the largest underground complex in the world. Maps of the Metro can be found in all the Metro stations. It links:

  • 10: Metro Stations
  • 1,200: Offices
  • 2,000: Stores
  • 200: Restaurants
  • 40: Banks
  • 1,600: Housing Units

In the Montreal Underground, one can find everything. There's bountiful shopping and dining. It even comes with its entertainment district where people can have a break from the shopping, wining, and dining. The Underground City links to the Place des Arts and the Musee d'art contemporain de Montreal. There is also a whole art network in the Underground City itself because of the Art Souterrain festival.

Did you know that there's an abandoned subterranean city under Seattle in Washington and there are tours of it?

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Cave Passages

In 2017 it was reported by CBC that a new underground passage (including a lake and stalactites) had been discovered under the city of Montreal. This was a new discovery and no one had been inside the caverns previously. The chamber underneath Canada's second city was described as cathedral-like and was formed over 15,000 years ago during the ice age.

  • Age: 15,000 Years Ago In The Ice Age

The passageways connect with the known Montreal's Saint-Leonard Cavern (the main portion of that cavern has been open to the public for decades). Although no one knew there was a massive section hidden behind a limestone wall.

It is at least 200 meters (yards) and around 6 meters high and 3 meters wide. The chamber is so deep that it reaches the aquifer. Cave explorers explore the aquifer with an inflatable canoe.

  • Length: 200 Meters (Yards)
  • Height: 6 Meters (Yards)
  • Width: 3 Meters (Yards)

The caverns were formed from the pressure of the glaciers during the ice age in a process called glacial tectonism. More information on visiting Montreal's Saint-Leonard Cavern can be seen on Capital Gems. The booking site for tours of the cavern appears to only be in French.

The terrain of Saint-Leonard Cavern is easy and guided tours are required to enter the cave. It is 50 meters long and dips 5 meters down. Hard hats and wet boots are provided.

Next time in Montreal check out its secrets beneath its streets hidden from view - both its glitzy Underground City and its ice age caverns.

Next: Are There Really Tunnels Under New York City? This Is What We Know