Black Mountain (Washington County, New York) Black Mountain (Washington County, New York) Black Mountain is a mountain located in Washington County, New York, of which its peak is the highest point. Isolated from the rest of the Adirondack Mountains by Lake George, Black Mtn. has the seventh highest topographic prominence of all the mountains in New York. Black Mountain stands within the watershed of Lake Champlain, thence into Canada's Richelieu River, the Saint Lawrence River, and into the Gulf of Saint Lawrence. The northwest and south sides of Black Mtn. drain into Lake George, thence into La Chute River, and Lake Champlain. The northeast side of
Champlain, New York connecting New York City to the south with Montreal to the north, via Quebec Autoroute 15. Champlain is approximately south of Montreal. According to the 2010 2010 United States census, the town has a total area of , of which is land and , or 12.90%, is water. Lake Champlain and the Richelieu River are on the east edge of the town, which shares a border with Grand Isle County, Vermont. The town line to the north is the international border with Saint-Bernard-de-Lacolle, Quebec, Canada. The Adirondack Northway (Interstate 87) is a major north-south highway that begins at the Canada–United