NIAGARA ESCARPMENT

also called Lake Ridge, ridge in North America that extends (with breaks) for more than 650 miles (1,050 km) from the Door Peninsula, in eastern Wisconsin, U.S., through the Manitoulin Islands, Ontario, Can., in northern Lake Huron, southward across the Bruce Peninsula, and then eastward around the southwestern end of Lake Ontario. It marks a portion of the shoreline (molded by glaciation and water erosion) of an ancient sea. The ridge crosses the CanadianUnited States boundary at Niagara Falls and terminates just east of Rochester, N.Y. Its forested crest, sloping steeply toward the north, stands from 250 to 1,000 feet (75 to 300 m) above the surrounding lowlands. Several rivers, notably the Niagara, have cut gorges through the scarp, leaving recessed cataracts, including the famous Niagara Falls. Such cities as Rochester have grown up adjacent to cataracts (Genesee Falls), taking advantage of the cheap power supply. The escarpment also shelters the intensive Niagara fruit belt along the southern shore of Lake Ontario.