Whales in the Egyptian desert? Why is Egypt's Wadi al-Hitan desert called the 'Valley of the Whales'?

Earth’s landscape has constantly evolved over the years, from vast raging oceans to shifting landmasses. Our planet has undergone a series of stages that shaped it into what we see today, hiding fossils of ancient organisms that roamed the planet millions of years ago beneath its layers.

Tucked 100 miles southwest of Cairo in Egypt's Western Desert, Wadi al-Hitan, known as Whale Valley, feels like stepping into a sci-fi novel. Once a shallow sea teeming with life 40 million years ago, this parched landscape now reveals evolution's playbook in plain sight.

What makes Wadi al-Hitan Egypt's whale fossil wonderland?

Wadi al-Hitan, or Valley of the Whales, is located in Egypt's Western Desert, 160 km southwest of Cairo, where fossilised whale skeletons litter the sands like relics from a lost ocean.

Once part of a shallow Eocene sea linked to the Tethys Ocean around 40 million years ago, the area preserved marine life before tectonic changes and erosion exposed hundreds of skeletons, according to UNESCO.

The site's magic lies in Archaeoceti fossils, or early whales bridging land and sea. According to UNESCO, "the valley provides some of the clearest evidence of this transformation, making it the most important site in the world for demonstrating the evolution of whales." Designated a World Heritage Site in 2005, it houses unmatched numbers, quality, and accessibility of fossils showing whales losing hind limbs.

Species like Basilosaurus, which grew up to 21 m long, and Dorudon appear with primitive skulls, teeth, flippers, and tiny legs—proof of their land-mammal roots. Serpentine carnivores swam in a vibrant ecosystem with sharks, rays, sirenians, reptiles, and fish from the Gehannam Formation.

Shining examples of evolution

These "youngest archaeocetes, in the last stages of losing their hind limbs," per UNESCO, are examples of the ocean shift. Other fossils reconstruct the ancient environment, from coastal shallows to rising seas. Over 1,000 whale skeletons, some with dolphins and sawfish, highlight a 42-million-year-old repository.

Today, it's no less than an open-air museum, with bones scattered or shallow-buried, slowly uncovered by wind.