Tren a las Nubes, Argentina Tren a las Nubes translates to “Train to the Clouds”, and you certainly shouldn’t expect anything less from your journey on this splendid heritage train service! It was given its name back in the 1960s when a film crew saw the train let out a stream of steam which did not immediately dissipate due to the cold mountain air in the region. The steam, which remained latent for a few moments resembled a cloud and thus the name was born!Running through Salta Province in Argentina, the train is one of the three highest railways in the world – and connects the Argentine Northwest to the Chilean border in the Andes Mountain Range which is over 4,220m over sea level!