Ask someone to name the largest desert in the world and almost everyone will say the Sahara. They are wrong, but they are wrong in an interesting way — and the answer to the question reveals something genuinely surprising about what a desert actually is. The Sahara is enormous (9.2 million square kilometres, roughly the size of the contiguous United States), but it is only the third-largest desert on Earth. The two larger ones are both polar.
A desert, in the climatological definition, is any region that receives very little precipitation. It does not have to be hot, and it does not have to be sandy. By that definition, the Antarctic and Arctic regions are the two largest deserts on the planet — each receiving less annual precipitation than many parts of the Sahara, despite being covered in ice. Once you accept this definition, the world ranking shifts in some unexpected ways. Here are the ten largest deserts in the world, ranked by area, with what each one looks like from above and what makes it distinctive.
1. Antarctic Desert — 14.2 million km²
The largest desert in the world is Antarctica. The continent receives less than 50 mm of precipitation per year on average across its interior — drier than many parts of the Sahara. The continent is covered in ice that has accumulated over millions of years, but the ice is essentially old snow that has not melted, not a record of significant ongoing precipitation. Some parts of Antarctica, particularly the McMurdo Dry Valleys, have not seen liquid water in more than two million years.
From above, Antarctica is a vast white expanse interrupted by the Transantarctic Mountains, the Antarctic Peninsula, and isolated rock outcrops called nunataks. The continent is roughly 1.5 times the size of the United States, and almost none of it has been touched by human beings. The interior is so featureless from satellite imagery that even experienced players in geography games struggle to place individual rounds within the continent itself.
2. Arctic Desert — 13.9 million km²
The Arctic desert covers the polar regions of North America, Europe, and Asia — roughly the area north of the Arctic tree line. It includes the Arctic Ocean's frozen sea ice, the high Arctic islands of Canada (Ellesmere, Devon, Banks), most of Greenland's surface, the northern coasts of Russia and Alaska, and Svalbard. Annual precipitation in many Arctic areas is below 250 mm — well within the definition of a desert.
Unlike Antarctica, the Arctic has substantial indigenous human population — the Inuit, Yupik, Sami, and other northern peoples have lived here for thousands of years. From above, the region is a complex mix of white sea ice, brown-grey tundra in summer, dramatic fjords (especially in Greenland and Svalbard), and patterned ground where freeze-thaw cycles have organised the soil into geometric polygons visible from space.
3. Sahara — 9.2 million km²
The largest hot desert in the world is the Sahara, stretching across North Africa from the Atlantic Ocean to the Red Sea and from the Mediterranean coast to the Sahel transition zone south of the Tropic of Cancer. It is roughly the size of the contiguous United States. The Sahara is famously sandy, but only about 20 percent of its surface is actually sand dunes (called ergs). The rest is hammada (rocky plateaus), regs (stony plains), salt flats, oases, and isolated mountain ranges like the Tibesti, Hoggar, and Aïr.
From above, the Sahara is one of the most visually varied deserts on Earth. The pale dunes of Erg Chebbi in Morocco, the dramatic red sand of the Tassili n'Ajjer in Algeria, the black volcanic rocks of the Tibesti in Chad, and the white salt flats of Chott el Djerid in Tunisia all look completely different. Identifying which part of the Sahara you are looking at from a satellite image is one of the highest skills a serious geography player can develop.
4. Arabian Desert — 2.3 million km²
The Arabian Desert covers most of the Arabian Peninsula — Saudi Arabia, Yemen, Oman, the United Arab Emirates, Qatar, Bahrain, and Kuwait. It contains the Rub' al Khali (Empty Quarter), the largest contiguous sand desert in the world. The Empty Quarter alone is larger than France, the Netherlands, and Belgium combined, with dunes that can reach over 250 metres in height — among the tallest sand dunes on Earth.
From above, the Empty Quarter looks like an endless sea of red-orange dunes, with no visible roads or settlements over enormous distances. The dunes are organised into massive linear formations called "longitudinal dunes," which run for tens or even hundreds of kilometres in roughly parallel lines.
5. Gobi Desert — 1.3 million km²
The Gobi covers northern China and southern Mongolia. Unlike the Sahara or the Arabian, it is a cold desert — temperatures swing from over 40 degrees Celsius in summer to well below minus 30 in winter. The Gobi is famous for the fossil discoveries made there in the 1920s, which transformed understanding of dinosaur evolution.
From above, the Gobi looks pale brown and grey, with extensive sand and gravel plains rather than the spectacular dunes of the Sahara or Empty Quarter. The desert is bounded by major mountain ranges — the Altai to the north, the Tian Shan to the west, the Qilian to the south — and contains substantial salt pans and dry lake beds.
6. Kalahari Desert — 900,000 km²
The Kalahari covers most of Botswana and parts of Namibia and South Africa. It is technically a semi-desert — it receives more rainfall than a strict desert definition allows in many areas, but the soil is so sandy that water drains away rapidly and the vegetation cover stays sparse. The Kalahari is the ancestral home of the San peoples, one of the oldest continuously inhabited regions on Earth.
From above, the Kalahari is more vegetated than most deserts — it appears in shades of yellow, red, and pale green rather than the bleached white of the Sahara. The famous Okavango Delta, where the Okavango River flows into the Kalahari and disperses into one of the largest inland deltas in the world, is one of the most visually striking landscapes visible from orbit.
7. Patagonian Desert — 670,000 km²
The Patagonian Desert is the largest desert in the Americas. It covers the southern part of Argentina, east of the Andes. The desert exists because the Andes block moist Pacific air from reaching the eastern slope — a classic rain shadow effect. Annual rainfall in much of Patagonia is below 200 mm.
From above, the Patagonian Desert is shaped by relentless westerly winds. The landscape is mostly steppe-like — sparse grasses and low shrubs across vast tablelands. The region is famous for its wind, its silence, and its almost total absence of human settlement — large portions of Patagonia have population densities below one person per square kilometre.
8. Great Victoria Desert — 650,000 km²
The Great Victoria is the largest of Australia's deserts, covering parts of Western Australia and South Australia. Together with the Great Sandy, Tanami, Simpson, and Gibson deserts, it forms part of the vast Australian desert system that covers nearly a fifth of the continent. The Great Victoria is named for Queen Victoria and was first crossed by European explorers in 1875.
From above, Australian deserts have a distinctive red colour caused by iron oxide in the soil. Linear dune patterns dominate much of the landscape, with dunes organised into roughly parallel rows that can run for hundreds of kilometres. The region is sparsely inhabited but has been continuously occupied by Aboriginal Australians for tens of thousands of years.
9. Syrian Desert — 520,000 km²
The Syrian Desert covers parts of Syria, Iraq, Jordan, and Saudi Arabia. It is sometimes referred to in older literature as the Hamad. The desert is a high plateau, mostly stone and gravel rather than sand, with isolated volcanic landscapes in some regions.
From above, the Syrian Desert is pale beige and brown, with sparse but visible ancient trade routes still traceable as faint lines across the landscape — including caravan paths used by traders moving between Damascus and Mesopotamia for thousands of years.
10. Great Basin Desert — 492,000 km²
The Great Basin Desert is the largest desert in the United States. It covers most of Nevada and large parts of Utah, Oregon, California, and Idaho. The desert sits in the rain shadow of the Sierra Nevada and Cascade ranges. It is a high cold desert — elevations are mostly above 1,200 metres, and winter temperatures regularly fall below freezing.
From above, the Great Basin has one of the most distinctive geological signatures of any desert: parallel mountain ranges separated by flat basins, the result of crustal stretching across the region over the past 30 million years. The pattern looks like ripples on water from orbit — a famous geological feature visible from space.
How to Identify a Desert From Above
If you play satellite imagery games regularly, deserts are some of the highest-volume rounds the game can produce — collectively, they cover well over a third of Earth's land surface. The key cues for distinguishing them are soil colour (red in Australia and parts of the Sahara, pale beige in central Asia, white in salt-flat regions), dune pattern (longitudinal in Arabia, transverse in parts of the Sahara, organised parallel in Australia), and surrounding context (Andes to the west for Patagonia, Tian Shan to the north for the Gobi, etc.). Few regions reward systematic visual learning as much as deserts do — and few teach more about how Earth's climate actually distributes water across the planet.
The next time you encounter a featureless tan landscape in a geography game, you can work through the elimination methodically: what colour is the soil? What is the dune pattern? Are there any mountain ranges visible at the edge of the frame? With practice, what looks like blank desert becomes one of the most readable landscapes on Earth — and the same systematic reading is what professional remote sensing analysts do every day when they monitor desertification, dust storms, and climate change across the planet's drylands.