The CN York Subdivision, or York Sub, is a

railway line Rail terminology is a form of technical terminology. The difference between the American term ''railroad'' and the international term ''railway'' (used by the International Union of Railways and English-speaking countries outside the United Sta ...

York York is a cathedral city with Roman origins, sited at the confluence of the rivers Ouse and Foss in North Yorkshire, England. It is the historic county town of Yorkshire. The city has many historic buildings and other structures, such as a ...

and

Durham Durham most commonly refers to: *Durham, England, a cathedral city and the county town of County Durham *County Durham, an English county * Durham County, North Carolina, a county in North Carolina, United States *Durham, North Carolina, a city in N ...

regions in the

Greater Toronto Area The Greater Toronto Area, commonly referred to as the GTA, includes the City of Toronto and the regional municipalities of Durham, Halton, Peel, and York. In total, the region contains 25 urban, suburban, and rural municipalities. The Greater T ...

. It runs for 25 miles between the Pickering Junction on the eastern edge of

Toronto Toronto ( ; or ) is the capital city of the Canadian province of Ontario. With a recorded population of 2,794,356 in 2021, it is the most populous city in Canada and the fourth most populous city in North America. The city is the ancho ...

, and the

MacMillan Yard The MacMillan Yard is the 2nd largest rail classification yard in Canada, after CN's Symington Yard in Winnipeg. It is operated by Canadian National Railway (CN) and is located in Vaughan, Ontario. It was originally opened in 1965 as Toronto Yard ...

Vaughan Vaughan () (2021 population 323,103) is a city in Ontario, Canada. It is located in the Regional Municipality of York, just north of Toronto. Vaughan was the fastest-growing municipality in Canada between 1996 and 2006 with its population increas ...

. Prior to the construction of the York Sub, CN traffic ran through the downtown core along the

CN Kingston Subdivision Canadian National Railway's Kingston Subdivision, or Kingston Sub for short, is a major railway line connecting Toronto with Montreal that carries the majority of CN traffic between these points. The line was originally the main trunk for the Gra ...

and through the

Union Station A union station (also known as a union terminal, a joint station in Europe, and a joint-use station in Japan) is a railway station at which the tracks and facilities are shared by two or more separate railway companies, allowing passengers to ...

area. During the 1950s, CN developed a plan to move traffic off of this line to a major new switching yard (MacMillan Yard) in what was then farmland north of the city. Traffic normally passing through downtown was switched onto the two new subdivisions, the Halton Sub connecting to the west, and the York Sub to the east. Construction of the York Sub took place between 1959 and 1965. Originally built in what was then farmland, the York Sub is now mostly urbanized in the Greater Toronto Area and has little room for expansion. The line spurs off northwest from the Kingston Sub at Pickering Junction in Pickering, with a bridge crossing over

Highway 401 King's Highway 401, commonly referred to as Highway 401 and also known by its official name as the Macdonald–Cartier Freeway or colloquially referred to as the four-oh-one, is a controlled-access 400-series highway in the Canadian provin ...

. The line briefly enters Toronto (passing through

Rouge National Urban Park Rouge National Urban Park is a national urban park in Ontario, Canada. The park is centred around the Rouge River and its tributaries in the Greater Toronto Area. The southern portion of the park is situated around the mouth of river in Toront ...

) and enters York Region, where it runs between

Steeles Avenue Steeles Avenue is an east–west street that forms the northern city limit of Toronto and the southern limit of Regional Municipality of York, York Region in Ontario, Canada. It stretches across the western and central Greater Toronto Area from ...

and Highway 7 to west of

Keele Street Keele Street is a north–south road in Toronto, Vaughan and King in Ontario, Canada. It stretches , running from Bloor Street in Toronto to the Holland Marsh. South of Bloor Street, the roadway is today known as Parkside Drive, but was originally ...

, where it continues west as the Halwest Subdivision at the wye tracks leading into the MacMillan Yard. It connects with the Newmarket Sub at Snider, with the Bala Sub at Doncaster, and with the Uxbridge Sub at Hagerman. Originally, there were

diamonds Diamond is a solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. Another solid form of carbon known as graphite is the chemically stable form of carbon at room temperature and pressure, b ...

with connecting wyes at each of these locations, but since the crossing with the Uxbridge Subdivision was grade separated, the connecting tracks at Hagerman were removed. The opening of the York Sub led to dramatically less traffic on the portion of the Kingston Sub between Pickering Junction and

in downtown Toronto, with a notable exception being

autorack An autorack, also known as an auto carrier (also car transporter outside the US), is a specialized piece of railroad rolling stock used to transport automobiles and light trucks. Autoracks are used to transport new vehicles from factories to ...

trains travelling to and from the Ford assembly plant in Oakville. This allowed

GO Transit GO Transit is a regional public transit system serving the Greater Golden Horseshoe region of Ontario, Canada. With its hub at Union Station in Toronto, GO Transit's green-and-white trains and buses serve a population of more than seven millio ...

to offer passenger trains along this route starting in 1967, on what is today known as the

Lakeshore East line Lakeshore East is one of the seven commuter rail lines of GO Transit in the Greater Toronto Area, Ontario, Canada. It extends from Union Station in Toronto to in Durham Region. Buses from Oshawa connect to communities further east in Newcastle, B ...

Metrolinx Metrolinx is a Crown agency of the Government of Ontario that manages and integrates road and public transport in the Greater Toronto and Hamilton Area (GTHA), which comprises much of Ontario's Golden Horseshoe region. Headquartered at Union Sta ...

has since purchased this section of the Kingston Sub, which has removed almost all of CN's traffic from the downtown routes. Metrolinx also purchased a portion of the Newmarket Sub from Bradford to Barrie to operate their

Barrie line Barrie is one of the seven train lines of the GO Transit system in the Greater Toronto Area, Ontario, Canada. It extends from Union Station in Toronto in a generally northward direction to Barrie, and includes ten stations along its route. From ...

. The Newmarket Sub, south of Bradford, and north of Rama, is still owned by CN. The significant amount of traffic on the York Sub led to delays on the Barrie line, backing up at the Snyder diamond. This led to the creation of a new grade-separated bridge to bypass the junction, allowing GO traffic to operate unhindered. Similarly, a grade-separated bridge was built at Hagerman, where the Uxbridge subdivision crosses the York subdivision. This bridge opened for service in December 2008.

References

{{DEFAULTSORT:York York Subdivision Rail transport in the Greater Toronto Area Rail infrastructure in the Regional Municipality of York Rail transport in Vaughan