Puente del Inca

Puente del Inca is a natural bridge high in the Andes of Mendoza, at about 2,700 metres above sea level, spanning the Las Cuevas river in a valley below the approach to Aconcagua. The arch is about 53 metres long and 28 metres wide, with its underside some 19 metres above the water. Its rounded, asymmetrical form is not rock in the ordinary sense: the structure is made of cemented debris and travertine, and its surface is stained in streaks of ochre, orange, yellow and green by mineral deposits and microbial growth from the hot springs that emerge beside it.

Its origin combines ice and hot water. During the ice ages, glaciers left great piles of rubble in the valley; mineral-rich water from the springs seeped through the debris and cemented it into solid rock. The river then cut a channel through the weaker lower layers, leaving the hardened upper part standing as a bridge. Charles Darwin crossed this way in March 1835 and sketched the bridge with its long stalactites hanging from the underside.

In the early twentieth century a thermal resort grew up here, with a grand hotel, bathhouses and a small church, served by the Transandine Railway that linked Argentina and Chile. An avalanche in 1965 badly damaged the hotel, and the resort was abandoned for good. The old railway station now holds a small museum of mountaineering. Since 1991 the bridge has been protected and visitors look at it from a viewpoint across the river; it became a provincial natural monument in 2005.

Getting there

The bridge stands beside Ruta Nacional 7, the main road across the Andes between Mendoza and Santiago, about 183 km by road from the city of Mendoza. Mendoza's Governor Francisco Gabrielli International Airport (MDZ) is about 105 km away in a straight line; Santiago's airport (SCL) on the Chilean side is about 103 km away but across the main range. The site lies between the two trailheads used for climbing Aconcagua.