the second largest of the Great Lakes, on the border between the US and Canada. Lake, U.S. and Canada. The second-largest of the Great Lakes of North America, it is bounded by Michigan and Ontario, and is about 206 mi (330 km) long with an area of 23,000 sq mi (59,570 sq km). Inflow comes from Lake Superior, Lake Michigan, and numerous streams; the lake discharges at its southern end into Lake Erie. It contains many islands, including Mackinac, and Saginaw Bay indents the Michigan coast. As part of the St. Lawrence Seaway, it supports heavy commercial traffic from April to December. The first of the Great Lakes seen by Europeans, it was explored by the French (1615-79), who named it after the Huron Indians