The Upper Peninsula is the northern of the two major peninsulas that make up the U.S. state of Michigan. It may also be referred to as the UP or Upper Michigan. The peninsula is bounded on the north by Lake Superior, on the east by the St. Marys River, on the southeast by Lake Michigan and Lake Huron, and on the southwest by Wisconsin.
The Upper Peninsula contains 29% of the land area of Michigan but just 3% of its total population. There are about 4,300 inland lakes and 12,000 miles (19,000 km) of streams. The peninsula is divided between the flat, swampy areas in the east, part of the Great Lakes Plain, and the steeper, more rugged western half, called the Superior Upland, part of the Canadian Shield.