Israelite slaves didn’t do it: Rediscovering a lost Nile branch

When they were slaves in Egypt for some 430 years, the Israelites built storehouses for Pharaoh, not the pyramids we know. However, according to researchers in Egypt, the US, and Australia, the pyramids visible in the desert today were not the only ones built.

Since the beginning of the Pharaonic era, the River Nile has played a fundamental role in the rapid growth and expansion of Egyptian civilization. Serving as their lifeline in a largely arid landscape, the Nile provided sustenance and functioned as the main water corridor for the transportation of goods and building materials.

For this reason, most of the key cities and monuments were built near the banks of the Nile and its peripheral branches. Over time, however, the main course of the Nile River laterally migrated, and its peripheral branches silted up, leaving behind many ancient Egyptian sites distant from the present-day river course.

Thirty-one Egyptian pyramids – including the Giza pyramid complex – may originally have been built along a 64-kilometer-long branch of the Nile that has long since been buried beneath farmland and desert. The findings, just reported in a paper in Communications Earth and Environment under the title “The Egyptian pyramid chain was built along the now abandoned Ahramat Nile Branch,” could explain why these pyramids are concentrated in what is now a narrow, inhospitable desert strip.

A long construction process

Built over a nearly 1,000-year period starting approximately 4,700 years ago, they are located on the edge of the inhospitable Western Desert, which is part of the Sahara. Sedimentary evidence suggests that the Nile used to have a much higher discharge, with the river splitting into several branches in places. Researchers had previously suggested that one of these branches may have passed by the pyramid fields, but this has not been confirmed.

The landscape of the northern Nile Valley in Egypt, between Lisht in the south and the Giza Plateau in the north, was subjected to a number of environmental and hydrological changes during the past few millennia, the team wrote.

“In the Early Holocene (about 12,000 years ago), the Sahara of North Africa transformed from a hyper-arid desert to a savannah-like environment, with large river systems and lake basins, due to an increase in global sea level at the end of the Last Glacial Maximum (LGM).

THE WET CONDITIONS of the Sahara provided a suitable habitat for people and wildlife – unlike the Nile Valley, which was virtually inhospitable to humans because of the constantly higher river levels and swampy environment. At this time, Nile discharge was high, which is evident from the extensive deposition of organic-rich fluvial sediment in the Eastern Mediterranean basin.”

Prof. Eman Ghoneim at the Earth and Ocean Sciences Department at the University of North Carolina at Wilmington and colleagues studied satellite imagery to find the possible location of a former river branch running along the foothills of the Western Desert Plateau, very near the pyramid fields.

They then used geophysical surveys and sediment cores to confirm the presence of river sediments and former channels beneath the modern land surface, indicating the presence of a former branch, which they propose naming ‘Ahramat’ (“pyramids” in Arabic). The authors suggest that an increased build-up of windblown sand, linked to a major drought that began approximately 4,200 years ago, could be one of the reasons for the branch’s migration east and eventual silt covering.

The discovery may explain why these pyramid fields were concentrated along this particular strip of desert near the ancient Egyptian capital of Memphis, as they would have been easily accessible via the river branch when they were built.

Additionally, the authors found that many of the pyramids had causeways that ended at the proposed riverbanks of the Ahramat branch, which they suggest is evidence the river was used for transporting construction materials.

The findings reiterate the Nile’s importance as a highway and cultural artery for ancient Egyptians and explain how human society has historically been affected by environmental change, the authors wrote. Future research to find more extinct Nile branches could help prioritize archaeological excavations along their banks and protect Egyptian cultural heritage, they concluded.