Signal Hill is a 150-acre (61 ha) open space preserve located in Canton, in the U.S. state of Massachusetts; it is centered on a 188-foot (57 m) rocky knoll by the same name. The property, acquired in 2005 by the land conservation non-profit organization The Trustees of Reservations, offers frontage on the Neponset River and views of Great Blue Hill and Downtown Boston from open ledges. The Signal Hill preserve also includes wetlands, open fields, and a car-top boating access point.