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Centre de commerce mondial

What Do You Know About the RESO?

The world’s largest underground network
Published on
November 28, 2017
Montréal’s Underground City offers a host of advantages, not least protection against bad weather and extreme temperatures. It also creates a separation between pedestrian and vehicle traffic and provides an incentive to use public transit. Discover it as though you were seeing it for the first time.

Martin Robitaille has been offering guided tours of the Underground City for 20 years. In that time, he’s realized that even Montrealers who pass through it daily know little about the history and idiosyncrasies of the Underground City, the largest such indoor network in the world.

“We often refer to it as the Underground City, when instead we should call it an indoor city,” says Martin Robitaille. “Because the Underground City is not just underground; it also has superb atriums, to go along with 10-storey buildings and raised passageways.”

Centre Eaton

Our discussion takes place beneath Christ Church Cathedral at the Promenades de la Cathédrale. What few people know is that we can thank the unstable soil at the foot of the cathedral for giving us this vast indoor space.

“The 19th century cathedral had to be raised on pilings to ensure it long-term survival. And because a substantial investment was required, the work was entrusted to a private developer in exchange for a 99-year lease. The new owner chose to build stores and restaurants beneath the structure,” says Martin Robitaille.

A city within a city

Pedestrian traffic at the McGill metro station is heavy, with some 11.3 million users transiting through it each year. Yet few stop to admire its artworks.

Métro McGill

“The Underground City is also the world’s largest underground art gallery,” says our guide. 

An estimated 80 or more artworks are spread out across the RESO, he goes on to tell me. Who has noticed the piece of the Berlin Wall in the middle in the Ruelle de Fortifications at the World Trade Centre Montréal? And who could even locate our World Trade Center on a map? Yet, it is part of the Underground City. 

Corridor menant au Centre de commerce mondial

“Citing Leonardo da Vinci, urban planner Vincent Ponte shared that vision of an indoor city where car and pedestrian traffic would be separated,” says Robitaille. “This location was ideal, as Place Ville-Marie came along and blocked the enormous pit dug by the CNR in the 1920s to build Central Station.”

By covering up this gaping hole on the urban landscape, the project also served to shift the city’s downtown away from its historical cradle in Old Montréal. Other commercial buildings were eventually connected to Place Ville-Marie as part of initiatives driven by separately funded commercial interests.

Place Ville-Marie

“The Eaton’s Centre, for example, invested $9 million to take advantage of the underground pedestrian traffic that the construction of the tunnel would generate,” adds our guide.

The geography of Montréal’s compact downtown – bordered, as it is, by Mount Royal and Old Montréal, then spanned by a pair of major underground infrastructures (the orange and green metro lines) – is ideal for expanding the Underground City. Indeed, some 80% of downtown office spaces and 35% of businesses are connected to the Underground City.


Centre de commerce mondial

Other than those of the STM, all the corridors in the RESO were built by private investors who provided the related signage, maintenance and security. This explains why there is no homogeneity across the Underground City, but rather an amalgam of corridors and public places, each with their own character.