Salar de Uyuni: the white horizon and the highest desert in the world

It’s 6:42 a.m. on the Salar in February — wet season — and the sky and the salt flat are essentially indistinguishable from each other. A thin layer of water, two or three centimetres deep, covers the entire 10,500 km² salt plain, and the morning clouds are reflected with no apparent distortion. Our 4x4, parked twenty metres away, is reflected in the water perfectly. Diego, the driver, has been doing this route for nineteen years. He pours coca tea from a thermos and we wait for the sun. This is the Salar at its most photographed.

Why I keep coming back

The Salar de Uyuni is the largest salt flat on earth and one of the most extraordinary geological features anywhere. It was formed by the desiccation of an ancient lake (Lago Minchin) over millennia; the salt crust is, in places, twelve metres thick.

In dry season (May–November), the surface is white and hexagonally-cracked, with isolated ‘islands’ of fossilised coral and giant cardón cacti. In wet season (December–April), a thin water layer turns it into the world’s largest mirror.

The surrounding southwest Bolivian altiplano — the high desert at 3,500–5,000 m — has the rest of the trip’s geology: coloured lagoons (Laguna Colorada, Laguna Verde), geyser fields (Sol de Mañana), high-altitude lava domes (the Stone Tree at Siloli), and the small village ruins.

How to do it

Most visitors do a 3-day 4x4 tour from Uyuni town, crossing from northwest to southeast across the Salar and the wider altiplano, ending at the Chilean border at Hito Cajón (where you cross into Chile and continue to San Pedro de Atacama).

Alternatively: a 1-day tour from Uyuni stays on the Salar only.

The 3-day tour is the worthwhile experience. The 4x4 has 5–6 passengers; the driver-guide; a cook for some segments; basic Bolivian-altiplano refugios for the two nights (basic but warm enough; expect bunk beds and shared bathrooms; the upper-end tours offer salt-block hotels).

What you’ll see (a 3-day itinerary)

Day 1: Uyuni → Train Cemetery (rusting steam locomotives outside town) → Salar surface → Incahuasi Island (the cactus-and-coral ‘island’ in the middle of the flat) → first sunset on the salt → overnight at a salt-block hotel at the edge of the Salar.

Day 2: Across the altiplano southward → Stone Tree at Siloli desert → Laguna Colorada (red-coloured lagoon with thousands of flamingos) → overnight at a basic refugio near the lagoon.

Day 3: Early start to Sol de Mañana geyser field at sunrise (4,800 m; the highest active geyser field on earth) → Laguna Verde (green lagoon under Licancabur volcano) → Chilean border crossing to San Pedro de Atacama.

Where to base yourself

Uyuni town is functional only; small Bolivian transit town. Don’t expect much.

San Pedro de Atacama (Chile, just over the border) is the easier and more pleasant base if you’re combining the Salar with Chilean Atacama Desert exploration.

For the high-end version, the Palacio de Sal or Luna Salada hotels are the salt-block luxury options on the edge of the Salar.

Where to eat

Food on the 3-day tour is provided by the operator — simple altiplano cooking (quinoa soup, llama meat, potatoes, rice). Vegetarian options should be requested at booking.

In Uyuni town, options are limited; the Minuteman Pizza is the long-running expat-friendly choice.

When to come

Wet season (December through March) for the mirror effect. The water is at its deepest in February.

Dry season (May through October) for the hexagonal-cracked white surface and the easier driving. The cardón islands are more accessible.

Shoulder weeks (late November and early April) sometimes give partial mirror in some sections — the best of both, with luck.

Practical notes

• Visa: 90 days visa-free for most Western passports.
• Money: Boliviano. ATMs in Uyuni are unreliable; bring cash (USD widely accepted).
• Altitude: 3,650 m on the Salar; 5,000 m at Sol de Mañana on day 3. Take it seriously. Acclimatise in La Paz (3,600 m) or another high town for at least a day before the tour.
• Operators: Tour quality varies considerably. Choose reputable operators (Quechua Connection, Red Planet Expedition, Salty Desert Aventours, Hidalgo Tours). The cheapest options sometimes cut corners on safety; the middle-tier is usually worth it. US$200–400 for a 3-day tour.
• Vehicle: 4x4 (Toyota Land Cruiser, usually). The roads are mostly dirt; expect rough going.
• What to bring: Layers (cold at night; can be near-freezing at the high refugios), sunglasses (the salt glare in dry season is intense), sunscreen, lip balm, water, head torch.

A final thought

The Salar de Uyuni is one of the most visually overwhelming places I have travelled to. The combination of the scale (you can see the curvature of the horizon), the colour (in wet season, the mirror; in dry season, the pure white), and the surrounding altiplano (the lagoons, the geysers, the volcanoes) makes the 3-day tour one of the great short trips of South American travel.

The trip is physically demanding — high altitude, long driving days, basic accommodation — but the photography and the sheer landscape scale are rare. Combine it with a few days in La Paz before and San Pedro de Atacama after; the resulting 8–10 day Bolivian-Chilean Andean trip is one of the best high-altitude experiences in the Americas.