St. Clair Rail Tunnel, Michigan

The St. Clair rail tunnel, under the St. Clair River, between Port Huron, Michigan, and Sarnia, Ontario, was the first underwater rail tunnel in North America. It was built in 1881 and closed in 1994, after a second, larger tunnel was built next to it.  The new tunnel was built to accommodate the taller intermodal rail cars, with double-stacked shipping containers, used for international shipping. Detroit has a rail tunnel under its river as well, but it is too small for these trains, and therefore sees less traffic. The new St. Clair Tunnel, more than a mile long, and 27 feet wide, was financed by CN, the Canadian National Railway Company, and is on a rail line connecting the large markets of Chicago and Toronto. It emerges next to an oil refinery on the Canadian side.