High Railway across the Puna

High Railway across the Puna is an original illustration set in Salta Andes, Argentina. It lies in the subtropics, where the climate is cold desert — arid, with freezing winters.

A short blue train crosses a tall open-lattice steel viaduct above a dry ravine on the high Puna. Ochre volcanic mountains surround pale salt-colored basins, sparse golden bunchgrass clings to rocky slopes, and an intense ultramarine sky spans the treeless plateau. The delicate bridge appears exposed against an immense landscape with almost no shelter or permanent surface water.

Why build a viaduct instead of descending into the ravine?

The viaduct carries the track across a deep side valley because descending into every ravine would make the railway too steep for locomotives; maintaining elevation is more practical than repeatedly climbing back out. Salt collects in pale closed basins because water has no route to the sea and evaporates in the dry air. Cold nights, aridity and strong exposure keep vegetation low even under bright sun. High steel engineering, volcanic color and salt-flat drainage together describe the Puna railway west of Salta, Argentina.

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