The great mystery of how the ancient Egyptians built the pyramids finally seems to be solved: ScienceAlert

Scientists have discovered a long-buried branch of the Nile that once flowed alongside more than 30 pyramids in Egypt, potentially solving the mystery of how ancient Egyptians transported the massive stone blocks to build the famous monuments.

The 40-mile-long arm of the river, which ran past the famous Giza pyramid complex among other sites, was hidden beneath desert and farmland for thousands of years, according to a study that revealed the find Thursday.

The existence of the river would explain why the 31 pyramids were built 4,700 to 3,700 years ago in a chain along a now inhospitable strip of desert in the Nile Valley.

The strip near the ancient Egyptian capital of Memphis includes the Great Pyramid of Giza – the only surviving structure of the Seven Wonders of the Ancient World – as well as the pyramids of Chephren, Cheops and Menkaure.

Archaeologists had long assumed that the ancient Egyptians must have used a nearby waterway to transport the vast materials used to build the pyramids.

“But no one was sure about the location, shape, size or proximity of this mega waterway to the actual pyramid site,” lead study author Eman Ghoneim from the University of North Carolina Wilmington in the United States told AFP.

The international team of researchers used radar satellite images to map the arm of the river, which they called Ahramat – “pyramids” in Arabic.

Radar gave them the “unique ability to penetrate the sand surface and produce images of hidden features, including buried rivers and ancient structures,” Ghoneim said.

Field studies and sediment cores from the site confirmed the presence of the river, the study in the journal said Communication earth and environment.

The once mighty river is becoming increasingly covered in sand, which may have started during a major drought about 4,200 years ago, the scientists suggested.

The Great Pyramid Mystery

The pyramids of Giza stood on a plateau about a kilometer from the banks of the river.

Many of the pyramids featured a “ceremonial elevated walkway” that ran along the river and ended at the valley temples that served as ports, Ghoneim said.

This suggests that the river “played a key role in transporting the enormous building materials and labor needed to build the pyramid,” she added.

Exactly how the ancient Egyptians managed to build such huge and long-lasting structures was one of the great mysteries of history.

These heavy materials, most of which came from the South, “could have been floated down the river much more easily” than transported overland, study co-author Suzanne Onstine of the University of Memphis in Tennessee, US, told AFP.

The banks of the rivers may have been the place where the pharaohs’ funeral entourage was received before their bodies were transferred to their “final burial site within the pyramid,” she suggested.

The river could also indicate why the pyramids were built in different locations.

“The flow and amount of water changed over time, so Fourth Dynasty kings had to make different decisions than 12th Dynasty kings,” she said.

“The discovery reminded me of the intimate connection between geography, climate, environment and human behavior.”

© Agence France Press