Lake Huron is one of the five Great Lakes of North America. Hydrologically, it comprises the easterly portion of Lake Michigan–Huron, having the same surface elevation as its westerly counterpart, to which it is connected by the 5-mile-wide (8.0 km), 20-fathom-deep (120 ft; 37 m) Straits of Mackinac. It is shared on the north and east by the Canadian province of Ontario and on the south and west by the state of Michigan in the United States. The name of the lake is derived from early French explorers who named it for the Huron people inhabiting the region. The Huronian glaciation was named due to evidence collected from Lake Huron region. The northern parts of the lake include the North Channel and Georgian Bay. Across the lake to the southwest is Saginaw Bay. The main inlet is the St. Marys River, and the main outlet is the St. Clair River.