In the mid-nineteenth century, the railway started spreading through southcentral and southwestern Ontario and was instrumental in establishing settlements in those regions. On December 3, 1855, the Hamilton and Toronto Railway (HTR) opened a station west of Toronto, just east of today’s Royal York Road. A village grew up around the railway station, and what would become the town of Mimico was born.
In the late 1880s, the HTR merged with the Great Western Railway, which subsequently merged with the Grand Trunk Railway (GTR). In 1906, the GTR opened its Mimico Yards not far west of the original Mimico Station, and for many years these yards were the main freight terminal for Toronto. In 1916, the GTR built a third Mimico Station building—the passenger building now being restored—near Church Street, now Royal York Road.
Another merger took place in 1923, when the GTR became part of the Canadian National Railway (CN). During the steam era, the Mimico yards were considered the main freight terminal for the City of Toronto. The Mimico CNR terminal was home to three separate but interlocking railway departments: the motive power department, which operated the roundhouse and operations of all locomotives at Mimico; the car department which looked after the inspection and repairs of the fleet of freight cars; the yard or traffic department which operated the maze of tracks and switches.
In the late 1960s, Canadian National stopped using Mimico Station as a passenger terminal. GO Transit, a railway system bringing commuters into Toronto, constructed a new small Mimico GO Station to the east of the 1916 building and Royal York Road. The 1916 building was used for some years to provide sleeping quarters for workers on the railway line, but eventually it fell into disuse and disrepair.