The Toronto, Hamilton & Buffalo Railway was incorporated in 1884 to construct a railway from Toronto, through Hamilton, to the International Bridge across the Niagara River and into Buffalo, New York. In 1890, the charter was amended allowing the eastern end of the line to terminate at Welland, Ontario, and connect with the Canada Southern Railway.
In 1892, the TH&B commenced operations through the acquisition of the Brantford, Waterloo and Lake Erie Railway. The BW&LE operated a line between Brantford and a connection with the Canada Southern Railway at Waterford and was in the process of extending the line eastward from Brantford towards Hamilton. The BW&LE depleted their capital funds during the extension to Hamilton resulting in the sale of the line. The TH&B completed the extension of the line into Hamilton along with construction of the line between Hamilton and Welland in 1895. The line between Waterford and Hamilton became the Waterford Subdivision and the line between Hamilton and Welland became the Welland Subdivision.
During 1895, the railway was sold to a consortium that included the New York Central, the Canada Southern, the Michigan Central and the Canadian Pacific Railway. Ownership of the line was distributed in the proportion 37.16% NYC, 13.89% CASO, 21.81% MCRR and 27.14% CPR. The Canada Southern and Michigan Central were subsidiaries of the New York Central so the actual ownership of the TH&B was 73% NYC and 27% CPR.
The next phase of construction was to be the line from Hamilton to Toronto. The surveyed route to Toronto closely paralleled the existing Grand Trunk Railway mainline. In order to avoid construction of a parallel line (and the potential loss of traffic to the competing line), the GTR granted running rights to the Canadian Pacific Railway between Toronto and Hamilton in 1896. That same year the TH&B constructed what became known as the Hamilton Connection between its line and the GTR at Hamilton Junction. The Hamilton Connection was subsequently leased to the CPR and became their physical connection to the TH&B.
In 1897, the TH&B obtained running rights over the Hamilton & Dundas Railway for the provision of freight service into the Town of Dundas. The H&D Railway, a local interurban line, ceased operations in 1923 and the TH&B acquired the former H&D right of way into Dundas to continue freight operations. The line into Dundas was known as the H&D Branch.
In order to tap into Hamiltonís expanding industrial sector, construction began on the Hamilton Belt Line in 1900. The Belt Line expanded with the construction of two additional branch lines in 1911 to allow access to all industrial sectors of the city, many of which were previously serviced exclusively by the GTR. Although the Belt Line was only six miles in length, it contained over 40 miles of yard and industrial sidings and would provide much financial sustenance to the TH&B over the years.
In 1914, the 14-mile Dunnville Subdivision was constructed southward from Smithville to the Town of Dunnville and extended five miles further to the shores of Lake Erie at Port Maitland in 1916. Access to Lake Erie allowed the creation of the TH&B Navigation Co. that operated between Port Maitland and Ashtabula, Ohio, from 1916 until discontinuance in 1932.
The TH&Bís final expansion occurred in 1927 when running rights were awarded over the Canadian National Railways to gain access to the industrial City of Port Colborne.
1935 saw the first abandonment of trackage when the Ridgeville Spur, a small four-mile branch extending off the Welland Subdivision just outside of Welland, was abandoned and the rails were removed in 1936.
The St. Lawrence Seaway Authority completed the construction of the present-day Welland Canal in 1972 resulting in the relocation of several rail lines in the area. The Welland Subdivision was realigned between Fenwick and Welland where a new yard was constructed and operated in conjunction with New York Centralís corporate successor, Penn Central. The new shared facility allowed the closure and removal of the original and independent TH&B and Penn Central operations located within the city. Welland Yard continues to operate today as a Canadian Pacificís marshalling facility for the Niagara Region.
In 1976, the United States Government amalgamated six bankrupt railroads, including the New York Centralís corporate successor, Penn Central, into a new entity called Conrail. In an effort to reduce debt, Conrail began shedding foreign investments including their controlling interest in the TH&B. In 1977, CP Rail acquired Conrailís 73% interest giving CP 100% control of the railway.
In 1985, CP Rail and Canadian National jointly acquired the assets of Conrailís Canada Division, the former Canada Southern Railway. CP Rail acquired exclusive ownership of the eastern end of the line between the TH&B connection at Welland and the international border crossings at Niagara Falls and Fort Erie, Ontario. While CP equipment was used to operate this portion of the line, known as CP CASO, the TH&B provided the managerial and administrative functions on CP Railís behalf.
The TH&B would continue to operate as a separate entity until 1987 when it was amalgamated into the Eastern Region of the London Division of CP Rail.
CP Rail abandoned the H&D Branch in 1988 with the Waterford Subdivision following in 1989. Also in that year, CP discontinued operations into Port Colborne, opting not to renew the running rights agreement over the CNR.
Today, the surviving portions of the TH&B, including the Hamilton Belt Line, the former Welland Subdivision and a portion of the Dunnville Subdivision operate as part of Canadian Pacificís Hamilton Subdivision in CPRís Southern Ontario Service Area.