Sierra Grande is an extinct shield volcano in northeastern New Mexico that rises 2,200 feet above the surrounding plain. It is part of the inactive Raton-Clayton volcanic field. Sierra Grande is the easternmost point in the United States that reaches an altitude of more than 8,000 feet above sea level (2,438 m).
U.S. Highway 64 and U.S. Highway 87 run along the north and east of the volcano with the town of Des Moines just to the northeast. To the northwest is the town of Capulin and Capulin Volcano National Monument, an extinct cinder cone volcano.