New York State Route 66 (NY 66) is a state highway in the Capital District of New York in the United States. The route begins at an intersection with US 9 and NY 23B in the Columbia County city of Hudson and ends at a junction with NY 2 in the Rensselaer County city of Troy. While both Hudson and Troy are located on the Hudson River, NY 66 follows a more inland routing between the two locations to serve several rural villages and hamlets, including Chatham and Sand Lake. NY 66 overlaps with U.S. Route 20 (US 20) and NY 43, two regionally important east–west highways, in Nassau and Sand Lake, respectively.