As surface space becomes more valuable, cities around the world are pushing transit, shopping and even utilities underground.
1. Singapore
Singapore is planning an increasingly underground city, with rail lines, roads, utilities and industrial facilities moved below ground to preserve scarce surface land. Its Underground Master Plan is intended to coordinate these projects rather than treating each tunnel separately.
2. Helsinki, Finland
Helsinki has spent decades developing underground infrastructure, including shopping areas, parking, utilities and transport facilities. The city maintains a detailed underground master plan covering hundreds of facilities beneath the surface.
3. Montréal, Canada
Montréal’s famous underground network connects shopping centers, office buildings, hotels, universities and transit stations. The pedestrian network now stretches for roughly 32 kilometers, allowing people to move through downtown without returning to street level.
4. Riyadh, Saudi Arabia
Riyadh is expanding underground transit as part of its transformation into a less car-dependent city. Its new automated metro network includes 176 kilometers of track and 86 stations, creating a huge underground layer beneath the growing capital. (Le Monde.fr)
5. Tokyo, Japan
Tokyo continually adds underground rail tunnels, pedestrian connections and commercial spaces because surface land is exceptionally valuable. Major station districts increasingly function as multiple-level cities, with shopping and transportation stacked below street level.
6. Toronto, Canada
Toronto is adding another underground layer through major subway projects. In 2026, tunneling began on the 15.6-kilometre Ontario Line, with twin tunnels running beneath downtown. The Eglinton Crosstown West Extension also completed major tunneling work this year.