North Yonge subway extension

outside Davisville station The Yonge subway line first opened on March 30, 1954, running between Union and Eglinton stations. The line was extended north along University Avenue to at Bloor Street in February 1963 as part of the Bloor–University subway project, creating a U-shaped Yonge–University line. The Bloor–University project also constructed the initial section of the Bloor–Danforth line, which opened in February 1966. ==Planning and design==

In 1959, an extension of the Yonge line north to Finch Avenue was proposed to be built sometime after a line along the proposed Spadina Expressway was completed. In mid-1961, the TTC drew up a plan to extend the line to Steeles Avenue in two phases. However, when Alderman Willam Archer asked for the plan to be released, the executive committee of Metro Toronto voted to keep it secret. In the 1960s, it was debated whether an extension on Yonge Street or one along Spadina should be implemented first, with supporters of a Spadina extension fearing overcrowding on the Yonge line if it were extended first. In October 1965, Metro Toronto voted in favour of constructing a Yonge extension to Sheppard Avenue first, despite North York and the TTC supporting an extension farther north to Steeles Avenue. Local opposition to the originally proposed route emerged in 1966. Near Hoggs Hollow, it was planned to be built above ground west of Yonge Street, but local ratepayers' associations preferred a route closer to Yonge and students of the local Loretto Abbey school were wary of its impact on the school's grounds. The TTC preferred the elevated route due to its lower estimated cost around $57 million, later adjusted to $67.8 million. In February 1968, TTC board member Ford Brand proposed extending the line farther from Sheppard Avenue to Finch Avenue after the commission found it would cost $7 to $10 million to add parking at Sheppard. TTC chair Ralph Day supported this extension, with the additional parking to be built on lands owned by Ontario Hydro. In 1968, the cost of the further extension to Finch was expected to be $22million for a cut-and-cover option west of Yonge or $26million for a tunnelled option below Yonge. The tunnel option was selected. The extension included four new stations: , , Sheppard, and , all named after their respective east–west cross streets. These stations were farther apart than stations elsewhere in the subway system and local bus service would continue to run on Yonge Street after the extension was complete. An additional station was planned at Park Home Avenue during the extension's original design but was not built as part of the initial project. The station was later built and opened in 1987 as North York Centre station. The tunnels were the first in the Toronto subway system to feature handrails for workers on the sides of tunnels. Additionally, four emergency exits were built due to the increased spacing between stations. One such exit would feature a horizontal tunnel to the nearby Don Valley Golf Course, designed that way to take advantage of the nearby slope down to the course and to prevent a climb to the surface along Yonge Street. ==Construction==

Construction of the project was originally expected to begin at the start of 1968, but the delayed completion of the Bloor–Danforth line prevented the extension's construction from starting. Additionally, local opposition to the initially proposed route delayed the extension's approval by Metro Toronto. In late 1969, the extension to Sheppard Avenue was expected to cost $79million and the cost of an additional extension to Finch had increased by $5million. At the time, Metro Toronto had agreed to fund all but $17million of the extension's cost, nearly half of which was to be covered by the Ontario government. It was expected to be complete around the end of 1971 despite labour disputes having disrupted work multiple times near , including at least one in 1968 due to safety concerns. the extension to Sheppard was delayed again to late 1972, with the extension to Finch delayed to early 1974. Costs of the initial section to Sheppard increased by $21million due to a surge in labour costs and soil problems at two locations. The section between York Mills and Sheppard was delayed again due to a labour dispute that had escalated to a strike by July 1971. The strike was resolved in January 1972, but a separate months-long strike began immediately after, again delaying work. The extension cost a total of $135million to build, less than the $140million estimated in 1970 but 20 percent higher than the $112million estimated for the whole extension in 1966. Additionally, 76 new subway cars were purchased for the extension in late 1969, costing $11.8million. Due to a shortage of subway cars when the extension opened, in early 1973, the TTC looked to extend its existing contract to an additional 88 subway cars to be used to relieve congestion on the existing network and to expand service both on the remainder of the extension to Finch as well as on the future Spadina branch of Line 1. ==Opening and operation==

platform's original 1973 wall tiles before being replaced in 2015 In 1972, a shortage of new subway cars prompted the TTC to recommend running only half of rush-hour trains on the extension once it opened to York Mills and to continue the practice once it had been extended to Finch. The other half would short turn at Eglinton. The first section of the extension to York Mills opened on March 31, 1973, with an opening ceremony held the day before. As suggested by the TTC, only half of rush-hour trains ran past Eglinton station, with headways of just over four minutes north of there compared to just over two minutes elsewhere on the line. All service at other times ran to York Mills. At the time, the remainder of the extension to Finch was reportedly 90 percent complete. Fears of overcrowding continued at the time, with the TTC proposing turning some trains back at Union station if necessary. In May 1975, the TTC stopped short turning afternoon trains at Eglinton, continuing the practice only during the morning rush hour. In January 1978, the Spadina subway project extended the western leg of the line to , which within two months appeared to be reducing crowding on the Yonge line. At the time, rush-hour trains either ran from to or from Wilson to Eglinton. The rush-hour short turns on the Yonge line ended in 1979, when the TTC started running all trains to Finch to reduce still-significant crowding north of Eglinton. The Spadina segment short-turns remained. ==Later Line 1 extensions and plans==

's terminus in Richmond Hill When the extension fully opened, North York mayor Mel Lastman supported extending the line further to the then–Metropolitan Toronto limit at Steeles Avenue, but it would have required the approval of the province's newly established Toronto Area Transportation Operating Authority. In the late 1980s and early 1990s, the TTC instead proposed turning the Yonge–University–Spadina line into a circle route, initially to be closed via a hydro corridor north of Finch Avenue but later to instead loop along Steeles Avenue allowing for subway service to York University. The loop proposal was abandoned by 2002 after the City of Vaughan successfully lobbied for a further extension of the Spadina branch to Highway 7, opened in 2017, to serve their planned downtown core. An extension of the Yonge line to near Highway 407 in York Region was proposed by Markham mayor Frank Scarpitti in 1993. By the end of 2009, an environmental assessment on the Yonge North subway extension (YNSE), which would extend the line further to Richmond Hill near Highway 407, was completed. The YNSE project was revised in the early 2020s and tunnelling on the extension is expected to begin in 2027. As of December 2025, the opening date for the extension is unknown. The project is owned and led by Metrolinx. ==References==