Washington County, New York is part of the Great Appalachian Valley (also known simply as the 'Great Valley') which is a long narrow valley strip often between tall mountain ranges. The county transitions from the Taconic Mountains to the Adirondack Mountains, and from the Lake Champlain Valley to Hudson River Valley. Much of the county is part of the slate valley of the Upper Taconic Mountains (Taghkanic, meaning 'in the trees'). The eastern boundary of Washington County is the New York–Vermont border, part of which is Lake Champlain. This is also the border with New England proper. The northern end of the county is
Champlain–St. Bernard de Lacolle Border Crossing Champlain–St. Bernard de Lacolle Border Crossing The Champlain–St. Bernard de Lacolle Border Crossing connects Champlain, New York and St-Bernard-de-Lacolle, Quebec on the United States–Canada border. It is the terminus of Interstate 87 in the US and Quebec Autoroute 15 in Canada. The route is the primary corridor between Montreal—less than 30 miles from the border—and New York City. The crossing is among the busiest in the US; more than two million travelers use it annually, including more than one half million during July and August. and is the second-busiest USA-Canada border crossing that is not located at a bridge. This