Ontario Line 3, Toronto’s latest subway expansion, reached a major milestone on May 28th, when the Province of Ontario announced that groundbreaking would begin at Queen Station. Located at the intersection of Yonge and Queen streets in the heart of the city, Queen Station will be one of four rapid transit interchanges on the 15.6km subway line. Extending from the Exhibition grounds in the west to Flemingdon Park in the northeast, the Ontario Line will be Toronto’s first new downtown subway line in over 60 years, targeted for completion in 2031.

Streetcar tracks at the intersection of Queen Street and James Street being torn out as excavation begins, June 1st, 2025, image by Urban Toronto forum contributor chickenfriedrice

Construction on the Ontario Line began in December, 2021 at Exhibition Station, and has since expanded across the city. In May, 2023, to enable preparatory works at Queen Station, three central blocks of Queen Street from Bay Street to Victoria Street were closed to traffic. This closure forced streetcars and motorists to divert onto nearby streets, leading to the reactivation of revenue streetcar service on Richmond, Adelaide, and Wellington, routes not used since the mid-20th century.

Streetcar tracks being rebuilt on Wellington Street East in September 2022 to facilitate diversions around the Queen Street closure, image by Urban Toronto forum contributor drum118

To facilitate construction around the clock in the densely populated downtown core, an acoustic shelter has been erected on Queen Street east of Yonge, standing over three storeys tall. Similar structures have been constructed on the site of Osgoode Station and the future King-Bathurst Station, where excavation work has been underway since 2024. These deep excavation sites are necessary to reach the alignment of the tunnel boring machines that will worm their way through the bedrock deep under the neighbourhoods of Queen West and the Fashion District.

The acoustic shelter erected within the Queen Street road closure, May 29th, 2025, image by Urban Toronto forum contributor reinventingthewheel

The late date at which full scale construction has begun on this crucial portion of the line has prompted fears of a repeat of the setbacks seen during the construction of the Eglinton Line 5 Crosstown LRT, Toronto's infamously delayed light rail line. Work on the interchange station at Yonge Street and Eglinton Avenue did not begin until 2016, a full five years after the earliest phases of construction began on the project. As of June 2024, Eglinton Station was the only station on the line yet to receive occupancy permits, with infrastructure relocation and deficiencies with the existing Line 1 station box blamed for the delays. Should such issues re-emerge during work on the Ontario Line, they are most likely to crop up at Queen Station. Nearly two centuries of development has left the soil at and around the bustling intersection criss-crossed with electrical lines, parking garages, sewers, a subway tunnel, and streetcar track beds.

Early excavation work underway at Eglinton Station in August 2017, a mere three years before the targeted opening date of the project, image by Urban Toronto staff member Edward Skira

Diagrams of the under-construction station display the extent of subterranean work required for trains to one day shuttle back and forth below Queen Street. Platforms will be located 40 metres below street level, requiring passengers to endure a total of five escalators when entering or exiting the station. The magnitude of excavation necessary to build the interchange, with its network of concourses, stairwells, ventilation shafts, and service areas, is staggering. By comparison, the existing Line 1 station box, built in the 1950s using the 'cut and cover' method, appears minuscule in the diagram below, with tracks located just a few metres beneath the roadbed.

Diagram of the Ontario Line station box at Queen Street, image courtesy of Metrolinx

Metrolinx initially stated its intention for Queen Street to be reopened to both streetcars and car traffic sometime in 2027, although any mention of a reopening date has been removed from Metrolinx's public notice regarding the closure. Only time will tell when streetcars will once again trundle down Queen Street, but it’s safe to say this iconic Toronto thoroughfare will be forever changed when the long-anticipated Ontario Line is complete.

UrbanToronto will continue to follow progress on this project, but in the meantime, you can learn more about it from our Database file, linked below. If you'd like, you can join in on the conversation in the associated Project Forum thread or leave a comment in the space provided on this page.

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