Essex is a town in Essex County, New York, United States overlooking Lake Champlain. The population was 671 at the 2010 census. The town is named after locations in England.The town is on the eastern edge of the county. It is 17 miles south-southwest of Burlington, Vermont, which is on the opposite shore of Lake Champlain, 32 miles south of Plattsburgh, 94 miles south of Montreal, Quebec, and 135 miles north of Albany, New York. Essex is inside the Adirondack Park.