Fort Frances, town (1991 pop. 8,891), SW Ont., Canada, on Rainy River, opposite International Falls, Minn. It is chiefly a lumbering center with sawmills and a pulp and paper factory. Tourism is also an important industry, with abundant fishing and hunting nearby. Formerly there was a Hudson's Bay Company post on the site, built (1820) near the ruins of an earlier (1731) French post, Fort St. Pierre.