🇧🇴 Bolivia · Altiplano and the Andean west
Some places seem to belong to another world, and the Salar de Uyuni is one of them. In the southwest of the Bolivian altiplano, at 3,660 meters, stretches the largest salt desert on the planet: more than ten thousand square kilometers of a white, flat, dazzling plain that disappears into the horizon, where sky and earth seem to merge. It is, without argument, Bolivia's most famous attraction and one of the most surreal and most photographed landscapes in the world.
The salt flat has two unforgettable faces. In the dry season it is an immense white blanket cracked into perfect polygons, where the lack of reference points allows those impossible perspective photos travelers enjoy so much, and where Isla Incahuasi rises up, covered in giant cacti. In the rainy season, a thin film of water turns the salt flat into a perfect mirror reflecting the clouds and the sky, one of the most magical images there is. And at sunset or at night, under a star-filled sky like no other, the experience becomes almost mystical.
This guide walks through the Salar de Uyuni with a practical eye: how to organize the 4x4 tours from the town of Uyuni, what the classic three-day circuit through the salt flat and the Reserva Eduardo Avaroa includes, when to go to see the mirror or the dry plain, how to get there and what to keep in mind about the altitude and the cold. It is one of those destinations that, once seen, you never forget.
The Salar de Uyuni is, above all, a geological wonder. It was formed by the evaporation of enormous prehistoric lakes that covered the altiplano tens of thousands of years ago, such as the ancient Lake Tauca and, before it, Lake Minchín. As those lakes dried up, they left behind a giant plain covered by a thick salt crust, which today is the largest salt flat in the world, at more than 10,000 square kilometers. Beneath that crust, in the brine, lies one of the largest lithium reserves on the planet, a key mineral for modern batteries, which has given the salt flat enormous strategic and economic importance for Bolivia. The region has been inhabited since pre-Hispanic times by Aymara peoples and, in the south, by the Lipes (from whom the name of the area, Los Lípez, derives), who knew and made use of the altiplano and its resources. The name 'Uyuni' comes from the town of the same name, founded in the late 19th century as a railway hub, when the railway linked the altiplano with the Pacific coast to ship out Bolivian minerals; from that era remain, among other things, the old locomotives of the famous train cemetery. Salt extraction has been traditional among the surrounding communities (such as Colchani), and today the salt flat is, above all, Bolivia's great tourist icon, a destination that draws travelers from all over the world. The full story is on our history page.
Read the full history ↓The department of silver and of the salt flats: home of the Cerro Rico that financed the Spanish Empire and of the Casa de la Moneda, of the Salar de Uyuni —the largest salt desert in the world and one of the great lithium reserves— and of the colored lagoons of the Eduardo Avaroa Reserve, on the highest and most desolate altiplano in the country, cradle of the hero Eduardo Avaroa.
Read the history of Potosí →No exact prices: a scale from $ (budget) to $$$$$ (luxury), with 2-3 options per category.
Origins, formation and what the sources say.
The Aymara say the Salar de Uyuni was born from a goddess's weeping. Tunupa, the most venerated mountain of the southern altiplano —today a 5,321-meter volcano dominating the northern edge of the salt flat—, was at the beginning of time a beautiful woman courted by many. Kusku won her and they lived together until another, Kusiña, seduced him and persuaded him to leave her. Kusku fled taking Tunupa's newborn child, and she, in despair, wept for days: her tears mixed with the milk flowing from her breasts and, spreading across the plain, formed the white sea we now call the Salar de Uyuni.
The legend is not tourist decoration: for many altiplano communities the mountain is still a living deity, and some hold that the salt flat should be called 'Salar de Tunupa' in her honor. Every rainy season, when a film of water covers the salt and turns it into the largest mirror in the world, locals say those are the goddess's tears, which never stopped falling.
It is a story that captures what makes this place unique: a landscape so extreme and unreal that it has always demanded mythical explanations. Science came later with its own —prehistoric lakes, evaporation, tens of thousands of years— and it turns out to be almost as astonishing.
The scientific explanation is measured in tens of thousands of years. During the Pleistocene, the Bolivian altiplano was covered by enormous lakes that took up much of the plateau. The oldest one to leave a clear trace was Lake Minchín, some 40,000 years ago; much later, between about 16,000 and 12,000 years ago, the basin filled again with Lake Tauca, a body of water that came to cover much of the southern altiplano at depths of up to 100 meters. When the climate turned drier and those lakes evaporated, they left behind plains covered by salt crusts: the Coipasa and Uyuni salt flats.
Uyuni is by far the largest: some 10,500 square kilometers of salt —bigger than the entire province of Tucumán—, at 3,660 meters above sea level. The surface crust, between 2 and 10 meters thick depending on the area, rests on alternating layers of brine and sediments that in some spots go deeper than 120 meters. And it is so extraordinarily flat —with height variations of less than a meter across its whole extent— that satellites use it to calibrate their altimeters.
Isla Incahuasi, with its giant cacti, is a direct relic of that watery world: a rock outcrop covered with the remains of algal reefs and fossil corals, which millennia ago was a real island surrounded by water and today is surrounded by salt. Walking its trails is, literally, walking on the petrified bed of a vanished lake.
Long before it became a tourist attraction, the salt flat was already known, travelled and used. The surrounding area was inhabited from pre-Hispanic times by Aymara-speaking communities and, to the south —in the region now occupied by the Reserva Eduardo Avaroa—, by the Lipes, the people who gave Los Lípez its name. These were societies adapted to one of the harshest geographies on the continent: freezing puna, scarce water, saline soils.
Salt was, from very early on, their resource and their currency. The communities on the edge of the salt flat cut it into blocks and loaded it onto llama caravans that went down to the valleys to trade it for maize, coca and fruit, on journeys that could last weeks and that kept running well into the 20th century. That ancestral economy survives in Colchani, the little salt village on the eastern shore, where families still scrape the crust, pile it into the characteristic cones you see from the road and process it by hand: it is estimated that some 25,000 tons of salt are extracted from the salt flat each year.
The salt flat itself was also a route: travelers crossed it from island to island —Incahuasi and the others served as refuge and as reference points in the roadless whiteness—, just as the tour 4x4s cross it today. In the local worldview, the white plain was never an emptiness: it was always a sacred place, watched over by the Tunupa, Kusku and Kusiña volcanoes, the protagonists of the old legend.
The town that gave the salt flat its name was born of a train. On 11 July 1889, by supreme resolution of president Aniceto Arce, Uyuni was founded at kilometer 610 of the railway line running up from Antofagasta, at a spot known as Posta Vieja. Arce —who besides being president was the owner of the powerful Compañía Huanchaca, with its silver mines at Pulacayo— had driven that railway forward as the only way to get Bolivian minerals out to the Pacific. Locals wanted to name the new town 'Aniceto Arce' in his honor; the president refused, and the place kept its Aymara name, which comes from 'uyu', corral or enclosure.
On 30 October of that same year the first locomotive reached the brand-new station, operated by The Antofagasta and Bolivia Railway Company Limited, with British capital. Uyuni became the great railway hub of southern Bolivia: the lines toward Chile, toward Oruro and La Paz, and toward Pulacayo and Potosí all crossed there. For half a century it was a prosperous town of workshops, railway workers and immigrants, nicknamed the 'Favorite Daughter of Bolivia'.
The decline came with the fall of silver and tin mining in the mid-20th century. Dozens of steam locomotives and wagons became obsolete and were dumped on the dead sidings outside town, where the dry, salty air rusted them without destroying them entirely. That is how the Train Cemetery was born, without anyone planning it: today the first stop on almost every tour, an open-air museum of the rise and fall of the Bolivian railway era.
Beneath the white crust the tourists walk on lies one of the greatest mineral treasures on the planet. The brine of the Salar de Uyuni holds 21 million tons of lithium resources, according to the certification carried out in 2019 by the US consultancy SRK Consulting; adding the Coipasa and Pastos Grandes salt flats, Bolivia reaches 23 million tons, one of the highest figures in the world. Lithium —the metal in the batteries of phones, laptops and electric cars— has turned this corner of the altiplano into a board on which global energy geopolitics is played.
Bolivia declared the salt flat a state reserve and in 2017 created the state company Yacimientos de Litio Bolivianos (YLB), the only one authorized to exploit the resource. After years of failed projects —including an agreement with the German firm ACI Systems, annulled in 2019 amid protests in Potosí—, the country signed contracts with Russia's Uranium One and the Chinese consortium Hong Kong CBC to build direct extraction plants. The government maintains that only 1.64% of the salt flat's surface will be exploited; local organizations and tour operators are closely watching the impact on water and landscape.
For travelers, this dimension adds a fascinating layer to the visit: the plain that looks like a mirror or a desert from another planet is, at the same time, the largest 'white gold' reserve on Earth, and the debate between tourism, environment and development is being had today in the very villages —Colchani, Río Grande, Uyuni— the 4x4s drive through.
Until the 1980s, the Salar de Uyuni was little more than a geological curiosity that the most adventurous backpackers crossed on salt trucks. Organized tourism was born in the 1990s, when the first agencies in Uyuni started offering 4x4 circuits and a local family put up the first hotel built entirely of salt blocks out on the plain: the Palacio de Sal, opened in the mid-1990s and dismantled in 2002 for sanitation reasons —there was no way to treat the waste out in the middle of the salt flat—, only to be reborn later on the shore, where it now competes with luxury salt hotels such as Luna Salada or Kachi Lodge.
Two things catapulted it to world fame. First, the photos: the impossible perspectives of the dry season and, above all, the 'mirror' of the rainy season, which in the Instagram era made the salt flat one of the most shared landscapes on the planet. Second, sport: on 10 January 2015, the Dakar Rally crossed the salt flat in a historic —and brutal— stage, with the wet salt wrecking engines, and president Evo Morales seeing the drivers off at Colchani before thousands of people; the Dakar passed through Uyuni again in 2016 and 2017, showing the white plain to millions of television viewers.
Today the salt flat is Bolivia's tourism engine: it receives hundreds of thousands of visitors a year, sustains the whole of Uyuni —agencies, hotels, restaurants— and is part of the great traveler routes of South America, connected with San Pedro de Atacama by the lagoon circuit. The goddess Tunupa, the Aymara would say, still weeps every summer; and every summer, the whole world travels to see her mirror.