This massive volcanic complex is the world's third highest active volcano, but remains largely unknown. Cerro Tipas (also known as Walter Penk or Cazadero), is located immediately SSW of its better known neighbor, Nevados Ojos del Salado, Earth's highest volcano. The summit of Tipas lies within Argentina, immediately south of the Chilean border. This complex of craters, cones, lava domes and lava flows covers an area of 25 km2. It displays a youthful morphology, and its latest eruptions were considered by de Silva and Francis (1991) to be of Holocene age.