in Salta, Argentina
Tren a las Nubes
The Train to the Clouds climbs to 4,220 meters through the Andes on one of the world's highest railways. This engineering marvel crosses 29 bridges and 21 tunnels with breathtaking viaduct crossings.
The Tren a las Nubes (Train to the Clouds) is a full-day heritage railway excursion that departs from Salta city and climbs into the Andes on one of the highest standard-gauge railways in the world, reaching a maximum elevation of 4,220 metres above sea level at the La Polvorilla Viaduct in the Puna de Atacama. The journey covers 217 kilometres from Salta in one direction and involves an ascent of more than 3,500 metres over the course of the trip, threading through the Quebrada del Toro canyon before emerging onto the high-altitude salt flats and volcanic plateau of the Argentine puna.
The engineering achievement that defines the journey is the series of zigzags and spirals — switchback sections where the train reverses direction to gain elevation on steep grades — and the 29 bridges and 21 tunnels constructed between 1921 and 1948 to overcome the extreme topography. The climax of the journey is the La Polvorilla Viaduct, a steel arch bridge 224 metres long and 63 metres high that spans a canyon at 4,188 metres altitude. Passengers disembark at the viaduct for photographs before the train reverses for the return descent.
The service is operated as a tourist service departing from the El Milagro terminal in Salta on Saturdays throughout the April to November season. The train includes first-class compartments with panoramic windows and airline-style seating, an on-board restaurant car serving meals and regional snacks, and medical personnel with portable oxygen for the predictable cases of altitude sickness that affect a proportion of passengers at 4,000 metres. The total journey takes approximately 15 hours.
The Quebrada del Toro canyon section in the morning light is particularly dramatic — the train winds through ochre and red rock walls with the Rosario de Cachi River far below, passing small indigenous communities that have existed along this route since long before the railway was built. The high-altitude stretch over the salt flats in the afternoon presents a completely different landscape of white salt, black volcanic cones, and deep blue Andean sky.
Hours: Seasonal departures April-November, Saturdays only
Best for: train enthusiasts, photographers, adventure travelers, bucket list seekers
Visit / Book / Contact
Location
Departs from Salta city, Salta Province
-24.7859, -65.4117 — View on map
Highlights
- One of the world's highest standard-gauge railways, reaching 4,220 metres at La Polvorilla Viaduct
- Dramatic La Polvorilla steel arch viaduct — 63 metres high and 224 metres long at 4,188 m altitude
- Engineered zigzag and spiral switchback sections through the scenic Quebrada del Toro canyon
- Transition from subtropical valley to Andean salt puna — two completely different landscapes in one journey
- On-board restaurant, panoramic windows, and medical oxygen for altitude management on a 15-hour excursion
Tips
- Book months in advance - limited departures
- Acclimatize to altitude before trip
- Bring warm clothing even in summer
- Train includes meals and medical oxygen
FAQ
How do visitors book tickets for the Tren a las Nubes?
Tickets are sold through the official website at trenalasnubes.com.ar. The service runs Saturdays only from April to November, with limited departures; advance booking of several weeks is strongly recommended, especially for the July–August peak period.
Is altitude sickness a concern on the Tren a las Nubes?
Yes — the train reaches 4,220 metres and a significant proportion of passengers experience headaches, nausea, or fatigue at altitude. Medical personnel travel on board with portable oxygen, which is provided free to affected passengers. Spending several days in Salta before the trip substantially reduces the risk.
Is the journey suitable for children?
The journey is suitable for older children and teenagers who can manage a 15-hour day. Young children are more vulnerable to altitude sickness, and parents should consult a doctor before booking. The long duration and limited movement space can also be challenging for children under eight.
Accessibility
The train has step-free boarding from platform level at Salta's El Milagro station. Visitors using wheelchairs or with significant mobility limitations should contact the operator at trenalasnubes.com.ar in advance; aisle space in the compartments is narrow. The La Polvorilla Viaduct stop involves a short walk on uneven gravel at 4,188 metres.
When to visit
April through November is the operating season; June through September delivers the clearest Andean skies and most vivid lighting on the salt flats and canyon walls. April, May, October, and November offer pleasant temperatures and fewer crowds than the July–August school holiday peak.