village, Cook county, northeastern Illinois, U.S. Summit is a suburb of Chicago, located about 13 miles (21 km) southwest of downtown. It lies on the Des Plaines River, straddling the watershed between the Great Lakes and the Mississippi River. Named for the ridge dividing the watershed, it was the site of a portage (route for carrying boats overland) used by the French explorers Jacques Marquette (Marquette, Jacques) and Louis Jolliet (Jolliet, Louis) in 1673. The location, designated a national historic site, marks the west end of the portage that connected the waters of the Great Lakes (and the St. Lawrence River) with those of the Mississippi River (and the Gulf of Mexico). An artery of travel used by Native Americans in their migrations and by fur traders, it was an early factor (preceding the Illinois and Michigan Canal) in Chicago's commercial growth. Although primarily a residential suburb, Summit has one of the world's largest corn (maize) products manufacturing plants. The village lies just west of Chicago Midway International Airport. Inc. 1890. Pop. (1990) 9,971; (2000) 10,637.