Isle Royale, the largest island in our Great Lakes, is located in the northwestern part of Lake Superior, 50 miles nw. of the Keweenaw Peninsula, 20 miles se. of the Canadian mainland, and 19 miles east of Grand Portage, Minnesota. Maximum elevation is 1300 feet, but most of the higher center ridge does not exceed 1,000 feet. Present altitude of Lake Superior is 602 feet.