Thunder Bay, on the north-east shore near the head of Lake Superior, is the furthermost port on the St Lawrence Seaway/Lake Superior accessible to sea-going vessels. It is the primary outlet for grain exported from the Canadian Prairies. Grouped around the docks are a whole series of gigantic grain elevators and storage
silos with a total capacity of about 4 million cu. m. (141 million cu. ft).
The city came into being in 1970 with the amalgamation of two existing communities, Port Arthur and Fort William. The latter began life as a trading post in the second half of the 17th c., the former being founded some 200 years later.