Sierra Blanca (also called the White Mountains) is a range of volcanic mountains in Lincoln and Otero counties of south-central New Mexico. It is the highest mountain in Southern New Mexico and the seventh highest peak in the state. The range is about 40 miles (64 km) from north to south and 20 miles (32 km) wide, and is dominated by Sierra Blanca Peak (White Peak), whose highest point is at 11,981 feet (3,652 m).