Tren a las Nubes at San Antonio des las Cobres

Tren a las Nubes is run as a tourist train from Salta (1187m) to Viaducto de la Polvorilla (4188m). It uses part of the Salta-Antofagasta railway line which used to connect both towns. Passenger trains ran until 1981, after that only freight trains used the track. The line was designed by American engineer Richard Fontaine Maury, construction started in 1921 and was finally finished in 1948. On the Tren a las Nubes section there are 2 horseshoe curves, 2 zig zags, 29 bridges, 13 viaducts and 21 tunnels.