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 (now the intersection of
NY 100 and
NY 120) and Rockdale Mills (close to what is now the
Briarcliff Manor border). As of the 2000 census, the community had a population of 1,210.