EastYorkTTCFan
Senior Member
It's part of the ventilation system for the new tunnel section to basicly in case of a fire to help remove smoke from the tunnel. They have been adding them to the existing parts of the tunnels as much as posable but most of line 1 and line 2 still rely on air from the open ends with some small ventilation fans in a few places.Apparently this has something to do with the Scarborough Subway Extension? Very clueless in regards to what this building is.