Toronto's underground system is the largest one in the world. 1200 retail locations, 30km long, 4M sq feet of retail space. It's very nice, all marble or polished stone everywhere, brightly lit, good food courts. Many many food courts. Almost all of it privately maintained and owned by each of the 50+ connected downtown towers and buildings.
In the summer, no one goes above ground it's too hot and humid. In the Winter it's too cold. For a few glorious weeks in Spring and Fall however, all the downtown residents and office workers find it hospitable to occasionally pop outside of their towers to enjoy the outdoors.
In the summer, no one goes above ground it's too hot and humid. In the Winter it's too cold. For a few glorious weeks in Spring and Fall however, all the downtown residents and office workers find it hospitable to occasionally pop outside of their towers to enjoy the outdoors.
https://en.wikipedia.org/wiki/PATH_(Toronto)