Step off the bus from Salta and the first thing the altitude does is reach into your chest. San Antonio de los Cobres sits at about 3,775 meters, high enough that newcomers learn to walk slowly and sip mate de coca, the coca-leaf tea that locals swear by for the headache that comes with thin air. Its name means Saint Anthony of the Coppers, a nod to the copper that drew miners to this corner of the Puna long ago. Today it is a quiet town of adobe and brick, capital of Salta's Los Andes department and home to a few thousand people who have made their lives where the oxygen runs short.
The journey here is the point. The road and the railway both leave the green Lerma Valley around Salta and grind upward through tightening switchbacks, climbing more than two and a half kilometers into a landscape that loses its trees, then its grass, then nearly its color. Tour buses pause along the way so travelers can stretch and take in pre-Columbian ruins scattered across the highlands. By the time the town appears on its bare plateau, the air is cold and brilliant, the sky a deeper blue than seems possible, and the lush valley below feels like another country entirely.
San Antonio de los Cobres is the high-country hub of the Tren a las Nubes, the Train to the Clouds, one of the highest railways on Earth. The line was an engineering feat of the early twentieth century, a route across the Andes built without tunnels or rack-and-pinion teeth, relying instead on switchbacks and zigzags to gain altitude. From town the train climbs a further few hundred meters to its showpiece: the La Polvorilla viaduct, a curving steel trestle 224 meters long that arcs across a desert ravine at roughly 4,200 meters, sixty-three meters above the ground. Passengers step out into the cold thin air to stand beneath it, dwarfed by the sweep of girders against an empty sky.
The town is a doorway to some of the most surreal scenery in the Andes. West toward Jujuy lie the Salinas Grandes, a blinding white salt flat so vast it confuses the eye, where the horizon dissolves and a small restaurant stands built from carved blocks of salt. The way there climbs the Cuesta de Lipán, a road of dizzying hairpin bends threading through mountains banded in mineral reds, ochres, and greens. It is a country of extremes, where the ground itself seems painted and the passes test both the lungs and the nerve.
For all that tourists pass through, San Antonio de los Cobres is first a working town, shaped by mining, herding, and the patient business of getting by at altitude. Llamas and vicuñas graze the surrounding flats, and the rhythms of life here owe more to the high Andean Puna than to lowland Argentina. The cold is constant, the wind relentless, the growing season nearly nonexistent. Yet people have chosen this place for generations, drawn by copper and held by something harder to name, a stubborn belonging to one of the highest inhabited corners of the country.
San Antonio de los Cobres lies at about 24.23 degrees south, 66.32 degrees west, at roughly 3,775 meters (12,385 feet) in the Puna de Atacama of Salta Province. From the air it appears as a compact grid of low buildings on an otherwise bare highland plain, with the General Belgrano rail line threading through; the La Polvorilla viaduct sits about 5 km west at 4,200 meters. The solitary cone of Cerro Tuzgle rises 45 km to the northwest. The nearest major airport is Martín Miguel de Güemes International (ICAO: SASA) at Salta, roughly 120 km southeast at 1,246 meters elevation. Expect clear, dry skies and excellent visibility most of the year, with strong winds and possible afternoon cloud buildup during the December-to-March summer monsoon.