Salar De Uyuni

Salar de Uyuni: The Salt Flat That Calibrates Satellites

At 10,582 square kilometres and 3,656 metres above sea level, the Salar de Uyuni is the largest salt flat on Earth. The surface is flat to within one metre across the entire expanse – a fact that NASA uses for satellite calibration. The crust averages 10 metres thick and rests on a brine lake with the world’s largest known reserves of lithium. The photographs you have seen are accurate. The place looks exactly the way it looks in photographs, and in person it is more disorientating than the photographs suggest, because the photographs lack the silence and the spatial disorientation of standing somewhere with no horizon.

Dry Season vs Wet Season

This is the central planning decision. The two seasons produce completely different landscapes.

From May through October (dry season), the salt is brilliant white and hard underfoot. The hexagonal crystal patterns are visible across the surface. Sunrise and sunset turn the flat pink and orange. You can drive to Isla Incahuasi, a rocky outcrop in the middle covered in giant cacti up to 10 metres tall, and stand in a landscape that resembles nothing else on Earth.

From December through March (wet season), a few centimetres of water floods the surface and creates the mirror effect that fills social media. The sky reflects in the thin water layer, the horizon disappears, objects appear to float above clouds. The photographs look surreal without manipulation. The downside: the flat is slippery, some areas become impassable, and tours are more constrained.

April and November are transitional and can go either way.

Getting There and Tours

Uyuni town is the base. Accessible by overnight bus from La Paz (about 10 hours), from Sucre (about 8 hours), or by small plane from La Paz on Boliviana de Aviación (about 1 hour). The buses are functional at this price point; the flights save significant time.

Most visitors book 3-day, 2-night 4WD tours from Uyuni. These head south from the salt flat through Eduardo Avaroa Andean Fauna National Reserve to see the coloured lagoons (Laguna Colorada, Laguna Verde), the geysers at Sol de Mañana (4,800 metres), and the hot springs at Termas de Polques. Cost: around USD 100 to 180 per person depending on group size and operator quality. Inspect the vehicle before committing; some operators maintain better equipment than others.

The Train Cemetery outside Uyuni – rusting 19th-century steam locomotives abandoned when the silver mining industry collapsed – is typically the first stop on tours and takes about an hour.

Altitude

This is the main physical concern. Uyuni sits at 3,700 metres; the southern altiplano reaches 5,000 metres. Acclimatise in La Paz or Sucre before arriving. Altitude sickness symptoms (headache, nausea, fatigue) are common in the first 24 hours. The temperature swings are extreme: warm by day, well below freezing at night year-round. Bring significantly more layers than you think you need for the multi-day southern tour.

Salt hotel accommodation on the flat itself is available – some lodges are built from salt blocks. Quality varies substantially.