The Tren a las Nubes, or Train to the Clouds, is a renowned tourist railway service in the province of Salta, Argentina. Its primary departure and arrival point is the city of Salta. The railway is famous for its remarkable engineering and the breathtaking journey it offers across the Andes mountains. The route ascends to extreme altitudes, with the line reaching its highest point at over 4,200 meters above sea level on the La Polvorilla Viaduct. This viaduct is a significant feat of engineering, constructed as a metal girder bridge spanning a deep gorge. The journey covers a substantial round-trip distance and takes passengers through dramatic and arid landscapes, including the Quebrada del Toro and the high-altitude desert plateau known as the Puna. The train's construction was a monumental task, initiated in the early 20th century to connect the Argentine Northwest with the border of Chile, overcoming immense geographical challenges. The service is operated using a diesel-electric traction system and is designed specifically for tourism, offering a unique perspective on one of the world's most spectacular railway lines. The experience focuses on the panoramic views and the historical significance of the railway's construction, which was vital for regional development.