5 Weird Discoveries Beneath the Sahara Desert

The Sahara Desert: an endless expanse of barren sand? Not so much. Though that’s what the world’s largest desert has come to look like in the popular imagination, the ever-shifting sands of the Sahara Desert are hiding some unbelievable things. This dynamic region was not always what it is now, and those who dig beneath its modern-day surface have uncovered some fascinating secrets. These are five of the most unusual things found beneath the Sahara Desert.

A Hidden “Ocean” of Ancient Water Trapped Deep Under the Sand

The Sahara Desert is just about the last place you’d expect to find water, but it’s actually concealing one of the largest supplies of groundwater, or aquifers, in the world. Aquifers are underground reserves of fresh water that are often vital to a region’s agricultural and daily-life needs, and beneath the Sahara Desert, you’ll find the Nubian Sandstone Aquifer System (NSAS), one of the oldest and largest such reserves in the world. It spans four countries and contains 20 times the size of all of North America’s Great Lakes combined.

That said, this is a fragile resource. Because aquifers cannot be renewed by rainfall like above-ground water sources, the water they contain is finite and single-use. It helps to think of water in aquifers like fossil fuels trapped underground: once extracted, it’s simply gone. In light of the immense need for water resources in this arid region, the NSAS is thus in danger of rapid depletion.

Whale and Crocodile Fossils That Prove the Sahara Was Once Underwater

Egypt is well-known for its Valley of the Kings - but would you believe the Egyptian portion of the Sahara Desert is also hiding a Valley of the Whales? Known in Arabic as Wadi al-Hitan, this seemingly barren landscape has yielded the incredible architectural discovery of prehistoric whale fossils. Tens of millions of years ago, the warm, shallow waters of the Tethys Sea covered this desert, playing host to the prehistoric whales whose bones now populate this otherwise lifeless UNESCO World Heritage Site.

But even before it was fully submerged, the Sahara wasn’t the desert we know today. About 120 million years ago, Northern Africa was covered by verdant wetlands, and paleontologists have discovered the fossils of several species of ancient saltwater crocodiles beneath the Sahara as proof.

Though they inhabited different ecological niches and geological eras, all of these finds point to one of the most fascinating aspects of the modern-day Sahara Desert: it’s only recently, as geological time goes, that it’s been much of a desert.

And After That, the Sahara Desert Was A Lot Greener

From about 14,000 to 10,000 years ago, Northern Africa experienced a biological heyday called the African Humid Period. Rivers, lakes, forests, wetlands, grasslands - the Sahara Desert didn’t look anything like it does today. And then, within a few millennia, the scale had flipped, turning that verdant stretch of the continent into the desert we know today. While we can’t be totally sure of the reasons for this sudden switch, scientists believe that it was too quick to have happened entirely on its own and suspect that overgrazing by livestock as human herders moved into the area may have indelibly shifted the region’s climate such that it dried out and became the desert we know today.

Ancient Cities Buried Beneath the Sand

Human habitation in the Sahara Desert hasn’t been limited to nomadic herders, though. Multiple large-scale cities and evidence of settled, agriculture-based societies have been found beneath the desert, including a former Egyptian capital. This site, the archaeological treasure trove of Tanis in the southern Nile Delta, was lost beneath the sand and rediscovered in the 19th and 20th centuries, and as a one-time royal capital, it has yielded rich insights into the ancient Egyptian society of its time.

But Tanis isn’t the only city beneath the sand, and the ancient Egyptians weren’t the only people building in the seemingly barren desert. The ancient city of Kerma in what is now Sudan was once the capital of a far-flung North African empire, but it declined and was lost to history after it was annexed by the Egyptians about 3500 years ago. Since its rediscovery, it’s told archaeologists much about the relationship between Egypt and its powerful but near-forgotten neighbors.

Evidence of 9000-Plus Years of Human Habitation

If new theories about human contributions to the desertification of the Sahara are true, then we know that humans have been there for a long time. But what archaeological evidence suggests that? The answer is a Neolithic monument that many liken to a North African Stonehenge.

A seasonal lake called Nabta Playa in southern Egypt offers ample proof that humans have been making their living in this area for over 9000 years. On the site is an arrangement of megaliths, the oldest of its kind, to align with the rising and setting sun during the solstice. It demonstrates that the nomadic herders who built the structure had a deep understanding of astronomical phenomena and hints at the advanced societies that sprang up in this region millennia ago.

The Sahara Desert is easy to imagine as static, a sandy expanse that has simply always been and always will be. But archaeology, ecology, and paleontology tell very different stories of a place that was once teeming with life in myriad forms - and one that has supported just as much human life. Dive beneath the sands, and you’ll find that this seemingly monotonous landscape isn’t nearly as lifeless as it seems.