Hudson River Estuarine Research Reserve System as the Hudson River National Estuarine Research Reserve. The Hudson River is navigable by large steamers up to Troy, and by ocean-faring vessels to the Port of Albany. The original Erie Canal, opened in 1825 to connect the Hudson with Lake Erie, emptied into the Hudson at the Albany Basin, just south of the Federal Dam in Troy (at mile 134). The canal enabled shipping between cities on the Great Lakes and Europe via the Atlantic Ocean. The New York State Canal System, the successor to the Erie Canal, runs into the Hudson River north of
Great Lakes some higher hills became Great Lakes islands. The Niagara Escarpment follows the contour of the Great Lakes between New York and Wisconsin. Land below the glaciers "rebounded" as it was uncovered. Since the glaciers covered some areas longer than others, this glacial rebound occurred at different rates. A notable modern phenomenon is the formation of ice volcanoes over the lakes during wintertime. Storm-generated waves carve the lakes' ice sheet and create conical mounds through the eruption of water and slush. The process is only well-documented in the Great Lakes, and has been credited with sparing the southern shorelines from worse