How One of the Driest Places on Earth Has Hosted Centuries of Life

A drop of rain is hardly news in most of the world. But in the Atacama Desert of northern Chile, it’s about as rare as the Detroit Lions reaching the Super Bowl. On average, the Atacama’s hyper-arid core, wedged between the Chilean Coast Range and the towering Andes Mountains, gets around 15 millimeters (0.59 inches) of rain per year—far less than even Death Valley, the driest place in the United States. One Atacama weather station purportedly recorded just 0.5 millimeters (0.02 inches) of rain per year from 1964 to 2001. At that rate, it would take well over a century to fill a coffee mug.

Though it is technically wetter than stretches of Antarctica, the Atacama Desert is often called the driest place on Earth. It’s certainly the driest place where people live, with a history of human habitation going back thousands of years.

Pablo Guerrero, a botanist at the Universidad de Concepción and the Instituto de Ecología y Biodiversidad in Chile, points out that in many ways the Atacama defies the popular image of a desert. For one thing, it lacks the blistering heat of, say, Death Valley or the Sahara. Like most of Chile, it’s also mountainous and contains a variety of habitats and climatic zones within its borders. “The Atacama Desert is spectacular and unusual,” Guerrero says in Spanish.

Here’s why it gets so little rainfall and how life survives in such an extreme landscape.

Along the Pacific coast, the Humboldt Current brings in cold, sub-Antarctic water, which limits the amount of evaporation from the ocean’s surface. The prevailing winds and coastal mountains then block what little moisture does get produced. Meanwhile, two parallel cordilleras of the Andes Mountains—separated by a high plateau—stop moisture from arriving from the east.

Linda Godfrey, a geologist at Rutgers University who has co-authored several papers on the Atacama, explains that this is often described as a “double rain shadow” effect. She notes that the western Andes don’t get much precipitation either. “So it’s a dry desert bounded by dry mountains,” Godfrey says.

When rain falls along the coast, it typically coincides with El Niño events. This was the case when Godfrey arrived in an Atacama port city in 2015 to find soaking-wet streets and leaking roofs, while mudslides occurred nearby. La Niña events, on the other hand, are associated with increased snowfall in the desert’s higher elevations.

Much of the Atacama is so dusty and desolate—in addition to being surrounded by active volcanoes—that Godfrey says it reminds her of Mordor from The Lord of the Rings. “It’s not a place that you would want to wander out into by yourself,” she says. Yet “it has a beauty to it as well.”

Because of its dryness, soil chemistry and otherworldly feel, the Atacama sometimes serves as an earthly stand-in for Mars. For example, the Mars scenes from Space Odyssey: Voyage to the Planets were filmed there, and it’s where NASA has long tested its Mars rovers, including during simulations of how to look for signs of life on the red planet.

Much of the Atacama is essentially devoid of visible life. In patches, however, the desert hosts a rich array of plant and animal species, many of which are considered evolutionary relics and found nowhere else on Earth. “They are living at the very limit of life,” Guerrero says. “From a scientific point of view, a lot can be learned from them.”

Each organism has its own specialized survival strategy, Guerrero says. The roots of the Copiapoa cacti, for example, absorb fog that drifts in from the coast, while some trees have roots deep enough to tap into groundwater supplies. Vegetation also grows alongside the area’s few streams, which are fed by springs and Andean snowmelt.

In the high desert, spiky grasses border salty lagoons that teem with crustaceans and the flamingos that feed on them. Wildflowers bloom after rare rains, including in 2025. After dying off, the flowers then survive as “seed banks for years or probably decades,” Guerrero explains, until the next time there’s enough water to germinate.

Many desert animals survive off the riches of the sea or live near freshwater sources. But there are also birds, reptiles, guanacos, foxes and even a small marsupial known as the yaca that roam the fog oases and other inland areas. As a 2026 study found, the soil even supports an array of roundworms.

Despite the challenges of living there, humans have inhabited the Atacama since as far back as 12,800 years ago. The earliest hunter-gatherers, who arrived at a slightly wetter moment in the desert’s history, are believed to have resided largely among groves of trees. Semi permanent villages appeared by around 4,000 years ago, says Estefanía Vidal Montero, an archaeologist at the Universidad Alberto Hurtado in Chile, and agriculture came to be practiced in floodplains.

“We don’t know much” about these prehistoric desert dwellers, Vidal Montero says, but they must have been “very attuned to the seasonality of water.” She adds that certain symbols reoccur in their rock art, pottery and textiles. Their language, however, remains a mystery.

The Chinchorro culture, renowned for creating some of the world’s first mummies around 7,000 years ago, lived in the Atacama along the coast. In the highlands, the ancient village of Tulor, known for its circular adobe structures, dates back some 2,500 years. Other Indigenous groups that have inhabited the Atacama include the Changos, Atacameños and Aymara.

The Inca Empire took control of the desert in the 1400s, to be displaced the following century by the Spanish. In the mid-1530s, Diego de Almagro, who had fought alongside Francisco Pizarro in Peru (and would later be executed by him), became the first known Spanish conquistador to enter what’s now Chile and cross the Atacama. “It’s written about as a failure,” Vidal Montero says of Almagro’s expedition. “He doesn’t find anything. He comes back defeated. A lot of his people die.”

During centuries of colonial rule, the Spanish never established much of a presence in the Atacama, especially outside the coast, Vidal Montero says. Nonetheless, the region’s Indigenous population drastically declined at that time (as occurred virtually everywhere in the Americas). After Spain lost control of its colonies in South America, the Atacama region ended up mostly under Peruvian and Bolivian control. But it was ceded to Chile in the 1880s following Chile’s victory in the War of the Pacific, which was fought over the desert’s valuable nitrate deposits, used in the production of fertilizer and explosives.

Vidal Montero says the Atacama was drastically transformed by industrialization. “There are a lot of resources that used to exist that no longer exist,” she says. “The forests would be one of them.”

Although the nitrate industry went bust following the invention of synthetic nitrate during World War I, the Atacama remains a mining mecca to this day, for everything from lithium to silver to copper. The tourism industry has also taken off, and some of the world’s most powerful telescopes are based there, with the lack of clouds and light pollution attracting amateur stargazers and professional astronomers alike.