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
Seven Second Summits of at least 100 km to reach Mount Logan. In South America, Ojos del Salado involves a short scramble while Aconcagua is just a walk. Horrell acknowledged that Ojos del Salado was more technically difficult, but considered Aconcagua a greater challenge because of physical demands. Aconcagua's base camp, at 4,500 m, is accessible by mule, but from that point, climbers must carry all of their supplies to as many as three higher camps before the final ascent. By contrast, Ojos del Salado is accessible by four-wheel-drive vehicles to 5,200 m; from that point, climbers need only carry supplies to a