Natural regions of Chile for reference purposes. These natural regions are ordered from north to south and reduced to five natural regions: Each has its own characteristic vegetation, fauna, climate, and, despite the omnipresence of both the Andes and the Pacific, its own distinct topography. Most of the region is covered by the Atacama Desert and has a dry arid climate. The coast range has peaks over 2000 m and ends in cliffs in the coast. There are large salt flats in the Intermediate depression and the Andes. Norte Grande has Chile's highest mountains including Ojos del Salado (6,891 m) but host also the
Aconcagua The colorful greenish, blueish and grey deposits that can be seen in the Horcones Valley and south of Puente Del Inca, are carbonates, limestones, turbidites and evaporates that filled this basin. The red colored rocks are intrusions, cinder deposits and conglomerates of volcanic origin. In mountaineering terms, Aconcagua is technically an easy mountain if approached from the north, via the normal route. Aconcagua is arguably the highest "non-technical" mountain in the world, since the northern route does not absolutely require ropes, axes, and pins. Although the effects of altitude are severe (atmospheric pressure is 40% of sea-level at the summit),