Toronto’s newest subway tunnel is starting to look more like something out of a sci-fi movie than a construction project.

Metrolinx recently gave the public a rare look inside the Scarborough Subway Extension, and one detail really stands out: the tunnel is so massive that you could fit a three-storey building inside it.

At nearly 11 metres wide, it’s officially the largest subway tunnel ever built in Canada.

 

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The 7.8-kilometre extension will connect Kennedy Station to c and McCowan Road, replacing the old Scarborough RT. Construction is now about 75% complete, with trains expected to start running around 2030.

Whether you’re excited about faster transit or just amazed by the engineering, it’s a pretty impressive glimpse at the future of Toronto’s transit system.