Lockport

City in northeastern Illinois, immediately north of Joliet and 48 km/30 mi southwest of Chicago; population (1990) 9,400. It is the site of locks that connect the Chicago Sanitary and Ship Canal with the Des Plaines River on the Illinois Waterway. Its economy is dominated by an oil refinery, grain elevators, and the Stateville Correctional Center, to the west. Products include cement and gravel products.

The city was founded in 1836 by the Illinois and Michigan Canal Commission as the headquarters for the building of the new canal. Some of the original locks are preserved. Lockport is now the home of Lewis College of Science and Technology (1930) and the Illinois and Michigan Canal Museum.

Lockport

City and administrative headquarters of Niagara County, western New York State, on the New York State Barge Canal, 33 km/21 mi northeast of Buffalo; population (1990) 24,400. It is the centre of the Niagara Frontier fruit belt, an agricultural area that produces apples, prunes, cherries, and peaches. Industries, sustained by Niagara Falls power, manufacture paper, textiles, plastics, car radiators and air conditioners, chemicals, and foundry products. Limestone and sandstone quarrying is also significant.

Founded in 1821, the city developed around a series of five double locks built along the original Erie Canal. The locks, built to overcome a 20-m/66-ft difference in level between Lake Erie and the Genesee River, were replaced by two modern locks when the canal system was enlarged at the turn of the century.