Underground City, Pedestrian network in Montreal, Canada

RÉSO, the Underground City, is a 32-kilometre pedestrian network beneath downtown Montreal, arranged in a U-shape with two north–south axes joined by an east–west axis. Its climate-controlled corridors link 10 metro stations, 2 bus terminals, about 2,000 stores, 200 restaurants, 7 hotels and 4 universities. The photographed passage has a polished floor, recessed ceiling lights, illuminated panels along one wall and escalators with dark handrails.

The network began in 1962 when the Place Ville Marie office complex was built and linked with underground corridors to the nearby train station. Expansion started in 1966 when the city metro stations were added and new connections to other buildings were built.

The name RÉSO, adopted in 2004, is a homophone of the French réseau (network), with the O styled after the Montreal Metro logo. Schematic maps bearing the logo appear throughout the corridors. For many Montrealers the network is simply a large mall linking Metro stations, and they may not realize they are inside it.

The corridors stay open daily, though some sections close earlier on weekends when offices are shut. You can find orientation maps at main junctions, but the many turns can be confusing if you are visiting for the first time.

Some sections near Place Ville Marie have glass ceilings that let daylight drop down into the lower floors and make you feel less underground. These light wells create an open feeling that is quite different from the narrow corridors you find in other parts.