A recent study published in the academic journal Communications Earth & Environment claims that the pyramids of Giza were constructed alongside an almost 40-mile-long artery of the Nile river that no longer exists today, having since been buried underneath desert and farmland.
The towering monuments at the Giza pyramid complex were built over a period of nearly 1000 years; some are more than 4500 years old. The complex is located between the ancient cities of Giza and Lisht in an area that now rests on the edge of the country’s Western Desert. The region’s inhospitable environment has long puzzled archeologists, who for centuries wondered how Egyptian workers managed to move the 2.5 ton stones that make up the pyramids.
In 2014, researchers from the University of Amsterdam suggested that the workers relied on engineering. Assuming they slid the stones over the desert surface, as depicted by a wall painting in the tomb of Djehutihotep, which was built around 1900 BCE, they speculated that the workers—172 per stone, according to the painting—may have wetted the sand in order to reduce friction, making the building blocks easier to pull.
Even though most of the stones are thought to have come from a quarry less than a mile away from the Great Pyramid of Giza, transporting them in this manner would have been a Herculean task—almost too Herculean for construction to have proceeded in this manner.
The study from Communications Earth & Environment proposes that the Egyptians used water to lighten their load. Investigating a theory that the Nile used to branch out into arteries that no longer exist today, study author Eman Ghoneim—an Egyptian-American geomorphologist at the University of North Carolina Wilmington—looked at satellite images of the Western Desert and conducted geological surveys, discovering a waterway that used to stretch alongside the now isolated pyramid complex.
Dr. Ghoneim and her co-authors speculate that the waterway, which they proposed to name “Ahramat,” after the Egyptian word for pyramids, was buried under sands swept up by a major drought around 4200 years ago.
To make the building process even easier, Egyptian workers appear to have dug causeways connecting the Ahramat to different construction sites, minimizing the distance they would have to move the stones through the use of manpower.
In addition to inspiring researchers to look for other dried-up branches of the Nile, the Communications Earth & Environment paper provides the clearest answer as to why so many of Egypt’s pyramids are located in one specific area—an area that, back in the day, was much more hospitable and easily navigable than it is now.