Paso de San Francisco is an international high mountain pass, at an elevation of 4.748m (15,577ft) above the sea level. This is one of the most important passes of the Andes mountains connecting Argentina and Chile. It's one of the highest mountain roads of Chile.
The pass connects the Argentinian province of Catamarca with the Atacama Region in Chile. In the Argentinian side, route N 60 ascends from Fiambala at 1.505 m above the sea level. in a deep valley formed by mountains which almost always overcome 5.000 m. In the last sinuous 20 km, the route climbs from about 4.000 m above the sea level. in Las grutas to more than 4.700 m at the border.
On the Chilean side, the road is gravel and sand, but on the Argentinian side, the road is paved. San Francisco Pass joins several Argentinean towns, located to the west of Tucumán, with the Chilean city of Copiapó, via the CH-31, an asphalt road with compacted salt. It is close to the highest volcano en the world, Ojos del Salado (6,891m).
On the Chilean side the route CH-31 connects Copiapo with the Chile-Argentinian border. On the way it passes next to Maricunga's salt flat on the Nevado Tres Cruces National Park and Laguna Verde. The area is surrounded by volcanoes and high peaks as the Cerro Falso Azufre (5.906 m above the sea level), the volcano San Francisco (6.018 m above the sea level), the Incahuasi (6.638 m above the sea level) and highest volcano in the world, Nevado Ojos del Salado (6.879 m above the sea level), among others.
Pic: Guillermo Moré