It includes a 4,500 metre underground section with three intermediate stations: York University Station, Steeles West Station (not included in this contract) and Highway 407 Station, as well as a train depot.

Highway 407 Station will be a newly-built underground station 165 m long, 22 m wide and 23 m deep; it will have a central platform and three floors, two below grade and one above grade, forming a Y-shaped building with a bus terminus and open-air parking for 600 cars.

The project will be built using two tunnel-boring machines (TBM) in three phases: the first, southward to the depot, will be 1,672 metres long; the other two will depart from the 407 Highway Station in different directions: southward to Steeles West Station (1,024 m) and northward to the end of the line (963 m).

The Toronto-York Spadina Subway Extension will provide a subway service between Toronto and York.

International experience in subway construction

FCC has extensive experience in building subways. It built over 126 km in 2009.

Late in 2010, it was awarded the contract for line 1 of Panama City Subway for 1 billion euro. At present it is also building: two sections (totalling over 4,000 m) of Singapore Metro for 334 million euro; part of New Delhi's new Metro network, amounting to close to 140 million euro; Athens Metro line 2, including the Peristeri and Anthoupoli stations; and the extension of Madrid Metro line 2 between La Elipa and Las Rosas, worth 157 million euro.