Mount Watatic is a 1,832-foot (558 m) monadnock located just south of the Massachusetts–New Hampshire border, in the United States, at the southern end of the Wapack Range. It lies in Ashburnham, Massachusetts and Ashby, Massachusetts. The 22-mile (35 km) Wapack Trail and the 92-mile (148 km) Midstate Trail both cross the mountain. The name is probably a corruption of the Native American term Wetu-tick, "wigwam brook", and probably applied first to the nearby large stream and thereafter to the mountain and the pond.