Do have a read of Kit Malthouse's excellent Times piece today on tunnels: ...Other cities have of course been burrowing for years. In Canada, they face not a space problem but an issue with the weather: when it's minus 25C, how do you keep people shopping? By digging of course.
Underneath downtown Toronto lies the PATH, an underground city stretching for 16 miles. With four million square feet of space, it is equivalent in size to 1.5 Empire State Buildings, employs 5,000 people in 1,200 shops and connects more than 50 surface buildings with five underground stations. Montreal has the same, only bigger. Paris, of course, has the Forum des Halles, a huge underground shopping mall, with a park on the roof. Delhi, Moscow, Tokyo and many others all take the same approach.
...The entire Hyde Park Corner interchange could be dropped below ground, and the three great parks of Central London could be united. You could walk from Parliament Sinquare to Queensway, about three miles, without crossing a road. Park Lane would be freed up for redevelopment, and a grand new public square could be created at Marble Arch.
...According to the AA, driving in a tunnel is twice as safe as on the surface and there are no pedestrians or cyclists to get in your way. Emissions can be collected and new techniques can