[...]
The
CN York Subdivision, or
York Sub for short, is a
railway line in
York and
Durham regions in the
Greater Toronto Area. It runs for 25 miles between the Pickering Junction on the eastern edge of
Toronto, and the
MacMillan Yard in
Vaughan.
Prior to the construction of the York Sub, CN traffic ran through the downtown core along the
CN Kingston Subdivision and through the
Union Station area. During the 1950s, CN developed a plan to move traffic off of this line to a major new switching yard in what was then farmland far to the north of the city. The switching yard emerged as the
MacMillan Yard, and the traffic normally passing through downtown was switched onto two new tracks, 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.
[1]
Originally built in what was then farmland, the York Sub is now firmly embedded in the
Greater Toronto Area and has little room for expansion. The lines pass from the Kingston Sub to York Sub at Pickering Junction, with a prominent bridge crossing over
Highway 401 in an area now surrounded by buildings, including the
Pickering Town Centre. The line runs just north of Steeles Ave to Yonge Street, then turns northeast to join John Street from Bayview to Woodbine, Esna Park Road/Alden Road between Woodbine to Warden, and 14th Avenue from Warden to Markham Road. It connects with the
Newmarket Sub at Snider, with the
Bala Sub at Doncaster, and with the
Uxbridge Sub at Hagerman. Originally, there ware
diamonds with connecting
wye tracks at each of these locations, but since the crossing with the Uxbridge Subdivision was grade separated, the connecting tracks at Hagerman were removed. [...]