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
Geography of New York (state) Geography of New York (state) The geography of New York state varies widely. Most of New York is dominated by farms, forests, rivers, mountains, and lakes. New York's Adirondack Park is larger than any U.S. National Park in the contiguous United States. Niagara Falls, on the Niagara River as it flows from Lake Erie to Lake Ontario, is a popular attraction. The Hudson River begins near Lake Tear of the Clouds and flows south through the eastern part of the state without draining lakes George or Champlain. Lake George empties at its north end into Lake Champlain, whose northern end