Millwood is a hamlet located in the town of New Castle, New York in Westchester County. It was originally settled as Sarlesville. The area now known as Millwood appears on 19th century maps as Merritt's Corners and Rockdale Mills. As of the 2000 census, the community had a population of 1,210.Miss America 1984 beauty pageant, model, actress and singer Vanessa Williams grew up in Millwood, but lives in New Castle's other hamlet of Chappaqua.Sarles' Tavern, also known as Granite House, was added to the National Register of Historic Places in 1979.