Great Lakes form a single, naturally interconnected body of fresh water, within the Great Lakes Basin. They form a chain connecting the east-central interior of North America to the Atlantic Ocean. From the interior to the outlet at the Saint Lawrence River, water flows from Superior to Huron and Michigan, southward to Erie, and finally northward to Lake Ontario. The lakes drain a large watershed via many rivers, and are studded with approximately 35,000 islands. There are also several thousand smaller lakes, often called "inland lakes," within the basin. The surface area of the five primary lakes combined is roughly equal to
Great Lakes Megalopolis Great Lakes Megalopolis The Great Lakes Megalopolis consists of the group of metropolitan areas in North America largely in the Great Lakes region and along the Saint Lawrence Seaway. To its south and west, it lies in the Midwestern United States, extending east into western Pennsylvania and Upstate New York, as well as north to Southern Ontario and the southern part of Quebec in Canada. It is the largest and most populated megalopolis in North America. At its most inclusive, the region cuts a wide swath from the Twin Cities in Minnesota to Pittsburgh, Pennsylvania and Rochester, New York. On