Champlain Valley southward into the Valley of Vermont. The Vermont Lowlands are primarily underlain by sedimentary rocks, especially limestone and shale, though metamorphic rocks such as marble and slate are also present. Lake Champlain is situated in the Champlain Valley between the Green Mountains of Vermont and the Adirondack Mountains of New York, drained northward by the Richelieu River into the St. Lawrence River at Sorel-Tracy, Quebec (northeast of Montreal). Major tributaries of Lake Champlain include Otter Creek and the Winooski, Missisquoi, and Lamoille rivers in Vermont, and the Ausable, Chazy, Boquet, and Saranac rivers in New York. Lake Champlain also receives
Lake of Two Mountains Lake of Two Mountains Lake of Two Mountains (French: Lac des Deux Montagnes) is part of the river delta widening of the Ottawa River in Quebec, Canada, at its confluence with the St. Lawrence River. Lake of Two Mountains has four outflows: Rivière des Mille Îles and Rivière des Prairies, bordering Île Jésus, and two branches of the Ottawa River, flowing into the St. Lawrence via Lake Saint-Louis, on either side of Île Perrot. The city of Deux-Montagnes is located on the lake's north shore, where it flows into Rivière des Mille Îles. The southwest portion of the city of