The St. Clair Tunnel was a railroad tunnel built under the St. Clair River between Sarnia, Ontario and Port Huron, Michigan. Opened in 1891, The St. Clair Tunnel Company was a subsidiary of Canada's Grand Trunk Railway and connected with its subsidiary, the Grand Trunk Western, in the United States. Here are several cards showing the tunnel entrances, the Port Huron Station, and the tunnel motors used in the operation.
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