Isle Royale National Park includes the large island for which the park was named and about 400 small nearby islands. They lie in the northwest part of Lake Superior. They have 338 miles (544 kilometers) of shoreline. The islands are part of Michigan, although they are nearer to Minnesota and Canada. For the area of the islands, see National Park System (table: National parks) .
Isle Royale, the largest of the islands, is 45 miles (72 kilometers) long and from 3 to 9 miles (5 to 14 kilometers) wide. This island has more than 30 inland lakes. Siskiwit Lake, the largest of the lakes, has several small islands of its own. Isle Royale is one of the few places in the world where copper is found in almost pure form. But mining is no longer carried on there.
One of the largest moose herds in the United States grazes on the island. The park is a refuge for other wild animals, including beavers, squirrels, rabbits, and timber wolves. Streams abound with freshwater fish. Many kinds of birds and flowers are found there. At least 30 kinds of orchids bloom in summer. Native trees include oak, maple, birch, and evergreens. The islands became a national park in 1931.