Portillo

by Thomas Lindinger, Martin Mergili, and Simon Schmidthaler

A historic journey on the roads of the Inca

After his exhausting ascent from Santiago de Chile, Pachacutec tells us about an ancient Inca tale, which is said to have occurred at the mountain lake Laguna del Inca seen in the title image. According to this tale, the Inca Prince Illi Yupanqui poured all his tears of sadness into this lake when his wife, the Princess Kora-Ile passed away in an accident. She died during a ceremonial activity which should have sealed their marriage. The body of the princess was left near the lake. The lake colour represents the colour of her eyes. It is said in the mountains aound Portillo that, in certain winter nights, the sadness of the Prince Illi Yupanqui is carried by the wind through the valleys and over the mountains. With tears in his eyes, Pachacutec continues his way across the Andes to Mendoza.

Do you believe this sad story? If not: try to explain the landscape in the photograph from the view of modern science. How could the Laguna del Inca have formed? And what is the function of the village in the centre of the image? You can also click on the Inca warrior to learn more about the road network of the Inca.

Show solution

Portillo is a ski resort at 2880 m asl. close to the Chilean-Argentine border. It was opened in 1949. In 1966, the World Championships in Alpine Skiing took place here - it was the first and only time that they were held on the Southern Hemisphere. Still today, Portillo is used for summer training by some ski teams from the Northern Hemisphere. In principle, the village consists of a large hotel and some holiday homes, located on a huge accumulation of coarse blocks which dams the valley and impounds a natural lake - the Laguna del Inca. Even though this accumulation of blocks, such as many others in the Aconcagua Valley, was in the past interpreted partly as moraine, and partly as rock avalanche deposit, today's opinion clearly favours an origin related to a prehistoric rock avalanche. From Portillo, the National Road 60 leads the international traffic in countless turns down to Juncal and further through the Aconcagua Valley towards Santiago, Viña del Mar, and Valparaíso.

Click into the title image to see the road section between Portillo and Juncal during day and during night.

Attention: railway tunnel above

The twisty section of the National Road 60 below Portillo has repeatedly been affected by debris flows. This happens particularly in spring, when snow melt releases a large amount of water which then flows down the gullies and erodes loose rock. A debris flow in November 2000 was related to a very specific triggering factor: meltwater had accumulated in a deteriorated tunnel of the abandoned railway line upslope from the road. That water was suddenly released, and the resulting debris flow hit a turn of the road. The photo shows the corresponding tunnel and the eroded gully with some remaining avalanche snow.

A racy descent from Portillo to Juncal

Click on the arrow to start the video.

Even though Portillo is known for downhill skiing rather than for car racing, this time lapse video shows the racy drive down the many turns overcoming the steep slope from Portillo to Juncal. However, it is not at all recommended to drive down at a similar speed in reality.

Downstream from Juncal, the road continues in western direction, eventually leaving the Andean mountains and proceeding towards the coast (visit the contribution on the coastal desert and the Christ Child).

Time lapse video: Claudia Blauensteiner

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Métraux, A. (2001): Reich der Inka. Stuttgart

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Wikipedia article on the Transandine Railway [Access source]

Wikipedia article on Portillo [Access source]

Spanish-language Wikipedia article on the Laguna del Inca [Access source]