The Black Range (also called the Devil's Mountains or Sierra Diablo) is an igneous mountain range running north-south in Sierra and Grant counties in west-central New Mexico, in the southwestern United States. Its central ridge forms the western and eastern borders, respectively, of the two counties through much of their contact. The range is about 55 miles (88 km) long from north to south and up to 18 miles (29 km) wide. The highest point is McKnight Mountain, at 10,165 feet (3,098 m). The Black Range lies almost entirely within the Gila National Forest. The Mimbres River originates from the mountain snow pack and run-off.