Great Lakes Megalopolis the Chicago-Rochester corridor, starting at the Detroit River but continuing east beyond Lake Ontario along the St. Lawrence Seaway to Quebec City and the Gulf of St. Lawrence. Several corridors have interstate highways but no comprehensive passenger rail service. These highway routes pass through both core and fringe areas of the Great Lakes megalopolis. The upper Great lakes region has a marine corridor that connects Lakes Superior, Huron, and Michigan. However, this route does not include parallel Amtrak passenger rail or interstate highway service. I-70 follows the southern fringe of the megaregion. It runs from Kansas City MO to just
Nipissing Great Lakes both Lake Erie and Niagara Falls would lack the volume of water needed to cut the channel through the Niagara limestone cap rock. Lake Erie was a nonglacial lake in this period. The third stage of nonglacial development ended the Lake Algonquin. A fourth stage was initiated when the upper lakes entered the Nipissing Great Lakes stage and that volume of water was diverted through the outlet at North Bay, Ontario. At this low stage, Lake Erie was to lower than present lake level and which lasted throughout the time of the Nipissing Great Lakes. The Lake Algonquin period of