Chicago's Dearborn Station. GTW was also part of a group that created and shared ownership in the Belt Railway Company of Chicago, which connects every rail line in the Chicago area. Canadian National By 1919, GTW's parent Grand Trunk Railway of Canada was suffering financial problems related to its ownership of the Grand Trunk Pacific Railway. The Canadian Government nationalized Grand Trunk and other financially troubled Canadian rail companies by 1923 and amalgamated them into the new government-owned entity, the Canadian National Railway. GTW would become a subsidiary of the new entity and was reincorporated as the Grand Trunk Western Railroad Company on November 1, 1928, when nearly all of its lines were formerly merged under the company. River tunnel GTW's predecessor Grand Trunk Railway also sought to expedite its rail service between Port Huron and Sarnia by constructing the world's first international submarine rail tunnel under the St. Clair River. The St. Clair Tunnel, completed in 1891, approximately long and hand-dug, allowed Grand Trunk to discontinue its ferry service across the river. The tunnel was the last link in GTR's complete mainline from Chicago through southern Canada. In 1992, Canadian National began construction of a new, larger tunnel next to the original tunnel to accommodate double-stacked intermodal containers and tri-level auto carriers used in freight train service. The new tunnel was completed in 1994 and dedicated on May 5, 1995. GTW also gained trackage rights in 1975 to use Penn Central's Detroit River Tunnel between Detroit and Windsor, Ontario. Penn Central's successor Conrail sold the tunnel to CN and Canadian Pacific Railway in 1985. Eventually, CN sold its share of the Detroit tunnel in 2000 after the new St. Clair tunnel was completed. The railroad's first major line abandonment came in 1951 when it abandoned about half of the former Toledo, Saginaw and Muskegon Railway line from Muskegon to Greenville, Michigan. That same year, Grand Trunk Western bought its headquarters building at 131 West Lafayette Avenue in downtown Detroit. At the end of 1970, GTW operated of track on of road, and that year it reported 2,732 million net revenue ton-miles of freight and 49 million passenger-miles. Grand Trunk Corporation After several years of Canadian National subsidizing the financial losses of Grand Trunk Western, a new holding company would be established by CN in 1971 to manage GTW. The Grand Trunk Corporation was created to shift full control of