Sierra Blanca (also called the White Mountains) is a range of volcanic mountains in Lincoln and Otero counties of south-central New Mexico. The range is about 40 miles from north to south and 20 miles wide, and is dominated by Sierra Blanca Peak, whose highest point is at . The peak is located 10 mi west-northwest of Ruidoso and 30 mi (48 km) north-northeast of Alamogordo.
The range serves as the headwaters for the Rio Ruidoso, Rio Tularosa, and Rio Bonito, as well as numerous arroyos draining into the Tularosa Basin, including Nogal Arroyo at the north end of the range.
Sierra Blanca Peak is the highest point in the southern half of New Mexico, and is one of the southernmost points at which alpine ecosystems occur in the United States. Rising 8000 feet (2400 m) above the adjacent Tularosa Basin, it has the highest prominence in the state, and is the southernmost high peak in the contiguous United States (all higher peaks are farther north). The peak can be seen for many miles, particularly within the Tularosa Basin, and is visible from as far away as Sandia Crest near Albuquerque.
The eastern foothills of the Sierra Blanca range include the town of Ruidoso, and the area has a number of popular hiking and camping destinations. The ski resort located on Sierra Blanca Peak (which is located mostly within the Lincoln National Forest and managed by the Mescalero Apache Indian Reservation) is called Ski Apache, and it is one of southern New Mexico's two ski resorts, the other called Ski Cloudcroft.