Chile — San Pedro de Atacama
Chile's San Pedro to Salar Trek is a formidable 70km, 4-5 day high-altitude expedition through the Atacama Desert's surreal landscapes. Descend dramatic canyons of the Domeyko Range and traverse volcanic highlands before reaching the shimmering Salar de Atacama. This challenging route offers unparalleled immersion in Earth's driest non-polar region, showcasing vast panoramas and remote wilderness.
Distance: 70.0 km
Elevation Gain: 2500 m
Difficulty: Challenging
Duration: 4-5 days
The San Pedro to Salar Trek is a formidable high-altitude expedition that traverses the most surreal landscapes of the Chilean Altiplano. Spanning approximately 70 kilometres over four to five days, this route offers an unparalleled immersion into the Atacama Desert—the driest non-polar place on Earth. Starting in the ancient village of Rio Grande and descending through the dramatic canyons of the Domeyko Range before culminating at the vast, shimmering expanse of the Salar de Atacama, the trek is a masterclass in geological diversity. Walkers will encounter multi-coloured mountains, prehistoric petroglyphs, hidden thermal springs, and the stark, crystalline beauty of the world's third-largest salt flat. This is not merely a hike; it is a journey through deep time, where the silence is absolute and the scale of the landscape defies human proportion.
The San Pedro to Salar Trek is a journey of profound contrasts. It begins in the precordillera (foothills) of the Andes, where the Rio Grande has carved a fertile green ribbon through an otherwise scorched landscape of red sandstone and white volcanic ash. As the route progresses southwards, the vegetation thins, and the geology takes centre stage. The trek navigates the "Valle del Arcoiris" (Rainbow Valley), famous for its hillsides streaked with mineral-rich shades of ochre, green, white, and violet, before entering the narrow, winding corridors of the Rio Salado canyon. Here, the water is heavy with minerals, and the silence of the desert is broken only by the occasional rustle of wind through the pampas grass.
The physical challenge of the trek is defined by two primary factors: altitude and climate. Starting at over 3,000 metres, hikers must contend with reduced oxygen levels from the outset. The terrain is often rugged, involving sandy riverbeds, rocky scree slopes, and ancient caravan trails that have been used for millennia. The climate is one of extremes; daytime temperatures can soar to 30 degrees Celsius under a relentless sun, while night-time temperatures frequently plummet well below freezing, especially in the higher reaches of the Domeyko Range. This thermal range requires meticulous preparation and a high degree of physical resilience.
The final stages of the trek provide a dramatic transition from the mountains to the basin. The descent into the Catarpe Valley reveals the lush oasis of San Pedro de Atacama from above, a sight that has greeted weary travellers for centuries. The journey concludes with a traverse across the northern fringes of the Salar de Atacama. This vast salt crust, covering over 3,000 square kilometres, is a landscape of jagged salt polygons and turquoise lagoons. Standing on the edge of the Salar, with the smoking cone of the Licancabur Volcano dominating the horizon, walkers realise they have traversed one of the most extraordinary environments on the planet. This trek is designed for those who seek solitude, geological wonder, and a genuine test of endurance in a landscape that feels more like Mars than Earth.
The Atacama Desert is not a barren void but a landscape rich with human history stretching back over 10,000 years. The San Pedro to Salar Trek follows portions of ancient "rutas caravaneras" (caravan routes) established by the Lickanantay people, also known as the Atacameño. These indigenous inhabitants were master architects of the desert, developing sophisticated irrigation systems and "pukaras" (fortresses) to protect their oases. The village of Rio Grande, where the trek commences, remains a bastion of traditional Atacameño culture, where stone houses and terraced agriculture reflect a lifestyle that has adapted to extreme aridity over centuries.
Throughout the trek, hikers will encounter tangible links to this past. In the Yerbas Buenas area, the rock faces are adorned with petroglyphs—ancient carvings depicting llamas, foxes, shamans, and celestial symbols. These artworks served as markers for travellers, indicating water sources, ritual sites, or territorial boundaries. The presence of these carvings highlights the historical importance of the Rio Grande and Rio Salado valleys as vital corridors for trade between the high Altiplano and the Pacific coast. Salt, textiles, and precious minerals were the currencies of this ancient network, transported by llama caravans that navigated the same passes used by modern trekkers.
The arrival of the Spanish in the 16th century introduced new layers to the cultural landscape. The colonial church in Rio Grande, with its cactus-wood roof and thick adobe walls, is a testament to the syncretism of indigenous beliefs and Catholicism. Later, the region became a hub for mining, particularly for copper and nitrates, which shaped the modern economy of northern Chile. However, the San Pedro to Salar Trek remains largely removed from industrial activity, focusing instead on the ancestral lands and the enduring spirit of the Lickanantay people. Walking this route is an act of following in the footsteps of ancient traders, explorers, and shepherds who have called this formidable desert home for millennia.
Want more background? Read extended notes on history and cultural context → Learn more
The Atacama Desert is a land of perpetual sun, but its seasons are distinct and carry significant implications for trekkers. The best time to undertake the San Pedro to Salar Trek is during the shoulder seasons of autumn (April to June) and spring (September to October). During these months, the daytime temperatures are manageable, typically ranging between 20 and 25 degrees Celsius, and the night-time temperatures, while cold, rarely reach the extreme lows of mid-winter.
Winter (June to August) offers the most stable weather and the clearest skies, which is ideal for the region's world-famous stargazing. However, walkers must be prepared for intense cold. At the higher elevations near Rio Grande, temperatures can drop to -15 degrees Celsius after sunset. The "Puelche" wind—a cold, dry wind from the east—can also be a factor, increasing the wind chill significantly. Despite the cold, many experienced trekkers prefer winter for the crisp air and the absence of any precipitation risk.
Summer (December to March) presents a unique phenomenon known as the "Invierno Altiplánico" (Altiplanic Winter) or the Bolivian Winter. During this period, moisture from the Amazon basin can spill over the Andes, causing sudden and violent thunderstorms, flash floods in the canyons, and even snow at higher altitudes. While the desert remains largely dry, the risk of being caught in a canyon during a flash flood is a serious safety concern. Furthermore, daytime temperatures in the lower basins near the Salar can exceed 35 degrees Celsius, making physical exertion during the midday hours dangerous. Consequently, trekking during the height of summer is generally discouraged unless under the guidance of local experts who can monitor weather patterns in real-time.
Day 1: Rio Grande to Valle del Arcoiris
Day 2: Valle del Arcoiris to Rio Salado Canyon
Day 3: Rio Salado to Catarpe Valley
Day 4: Catarpe to San Pedro de Atacama and Northern Salar
Day 5: Salar Exploration and Conclusion
Important Notes:
The San Pedro to Salar Trek requires meticulous logistical planning due to its remote nature and the harshness of the environment. The most critical aspect of preparation is acclimatisation. San Pedro de Atacama sits at 2,400 metres, while the trek begins at over 3,200 metres. It is strongly advised to spend at least 48 to 72 hours in San Pedro before starting the trek, engaging in light activity and staying hydrated to avoid altitude sickness (soroche). Coordination of transport is also essential; the trailhead at Rio Grande is not served by public transport, so a private 4x4 drop-off must be organised in San Pedro.
Physical fitness is paramount. While the elevation gains are not extreme compared to Himalayan treks, the combination of thin air, heavy packs (if self-supported), and the dehydrating effect of the desert makes every kilometre feel significantly harder. Trekkers should be comfortable walking 15–20 kilometres per day on uneven, often sandy terrain. It is also vital to inform the local Carabineros (police) or a reputable trekking agency of your itinerary and expected return time, as mobile signal is non-existent once you leave the immediate vicinity of San Pedro.
This is primarily a wilderness trekking experience, and formal accommodation along the route is virtually non-existent. Trekkers must be prepared for wild camping for the duration of the journey.
Camping and Shelters:
Facilities Provided:
Currently, there is no formal "permit" required by the Chilean government to walk the San Pedro to Salar Trek. However, much of the land is managed by local indigenous communities (Comunidades Atacameñas), and respecting their sovereignty is crucial for the continued accessibility of these routes. In some areas, such as the Yerbas Buenas petroglyphs or the Pukará de Quitor, a small entrance fee (usually between 3,000 and 10,000 Chilean Pesos) is charged by the local community to fund conservation and maintenance.
Local Regulations and Access:
Costs and Logistics:
Detailed route notes, maps, logistics & tips for the San Pedro Salar Trek (PDF).
Precisely traced GPX for the San Pedro Salar Trek, ready for your GPS or favourite mapping app.
San Pedro de Atacama is the adventure capital of Chile. Consider these activities to complement your trek:
Altitude Sickness (Soroche): This is the primary risk on the San Pedro to Salar Trek. Symptoms include headache, nausea, dizziness, and fatigue. The only cure for severe altitude sickness is descent. Trekkers should monitor themselves and their companions closely. Drink at least 4 litres of water daily, avoid alcohol, and consider coca tea (a local remedy) or medication like Diamox after consulting a doctor.
Dehydration and Heat Stroke: The humidity in the Atacama is often near zero. You will lose moisture through breathing and perspiration without even realising it. Dehydration can happen rapidly and exacerbates altitude sickness. Wear lightweight, long-sleeved clothing to protect against the sun and reduce moisture loss. Avoid trekking during the hottest part of the day (12:00 PM to 4:00 PM) if possible.
Flash Floods: During the Altiplanic Winter (January–March), dry riverbeds can become raging torrents within minutes due to storms in the mountains. Never camp in the bottom of a narrow wash or canyon if there are clouds over the Andes. Always look for high ground for your campsite.
Navigation Hazards: The desert is a disorienting place. Landmarks can look identical, and heat haze can distort distances. There are no blazed trails. Relying solely on a smartphone for navigation is dangerous as batteries fail in the cold and screens can be impossible to read in the bright sun. Always carry a backup power bank and a physical map/compass.
Wildlife: While generally safe, be aware of the "Vinuca" (kissing bug), which can carry Chagas disease, though it is rare in trekking environments. Pumas exist in the mountains but are extremely elusive. The most common "danger" is the territorial nature of some shepherd dogs near Rio Grande; keep your distance and do not provoke them.
Yerbas Buenas Petroglyphs: Located near the junction of the Rio Grande and the Rainbow Valley, this is one of the most significant rock art sites in Chile. Thousands of carvings dating back to the Formative Period (500 BC – 500 AD) depict the worldview of ancient desert dwellers. Spend an hour wandering the volcanic outcrops to find hidden depictions of monkeys and dragons, which suggest ancient trade links with the Amazon.
Valle del Arcoiris (Rainbow Valley): A geological marvel where the hillsides are composed of different mineral layers. The deep reds come from iron oxide, the greens from copper carbonate, and the whites from calcium carbonate and gypsum. The best time for photography is the "golden hour" before sunset when the colours become incredibly vivid.
Pukará de Quitor: This 12th-century stone fortress was built to defend the San Pedro oasis from invading forces. It was the site of a major battle between the Atacameños and the Spanish conquistadors in 1540. Climbing to the top of the ruins provides a strategic view of the entire San Pedro river basin and the trek route you have just completed.
Laguna Cejar: Located on the northern edge of the Salar, this lagoon has a salt concentration higher than the Dead Sea. While trekking past, you can pay for entry to float effortlessly in the turquoise waters while looking out at the Andes. It is a surreal sensory experience after days of dusty trekking.
The Salt Caves of the Cordillera de la Sal: If you have extra time near Catarpe, explore the narrow "quebradas" (gorges) where the walls are made of pure rock salt. You can hear the salt "cracking" as it expands and contracts with the temperature changes.
The Atacama Desert is an incredibly fragile environment. Because of the lack of moisture, biological decomposition happens at an extremely slow rate. A piece of orange peel or a tissue can remain visible for decades. Furthermore, the desert crust (cryptobiotic soil) is a living community of cyanobacteria, lichens, and mosses that prevents erosion; a single footprint off-trail can destroy centuries of growth.
Specific LNT Guidelines for the Atacama:
