Ville Intérieure, originally uploaded by Fabiano Rebeque.

One of the many pathways of Montreal's Underground City. With over 32km of tunnels spread over most of the city's downtown, it's the largest underground complex in the world.

The connections are considered tunnels architecturally and technically, but are air conditioned and have lighting as good as any building's liveable space does. Many tunnels are large enough to have shops on both sides of the passage. With over 32 km (20 mi) of tunnels spread over more than 12 km2 (4.6 sq mi), connected areas include shopping malls, apartment buildings, hotels, condominiums, banks, offices, museums, universities, seven metro stations, two commuter train stations, a regional bus terminal and the Bell Centre amphitheatre and arena. There are more than 120 exterior access points to the underground city. In winter, some 500,000 people use the underground city every day.

(Text by Wikipedia)