The Tren A Las Nubes Train, Salta Province, Argentina

The Tren a las Nubes today
After several years of refurbishing, the train was again open to the public on 6 August 2008, it is operated by a private company named Ecotren.
Currently, the train leaves Salta station for the 15-hour, 434-kilometre (270 mi) round trip to the viaduct La Polvorilla, located 4,220 m (13,850 ft) above sea level. The curved viaduct is 224 m (735 ft) long and 70 m (230 ft) high. Once the train has left Salta, it firstly enters the Valle de Lerma, and then the Quebrada del Toro, before reaching the puna. It is known as the Train of the Clouds because clouds can often be seen around and under the bridges and slopes of the landscape through which the railway passes.