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Why Egypt’s pyramids are so isolated — it’s all about the Nile

Why Egypt’s pyramids are so isolated — it’s all about the Nile
The Giza pyramids. (Photo: Wiki Commons)

Between the town of Lisht and Giza stand 30 immense pyramids, seemingly marooned, in the sands of Egypt’s Western Desert. Why there? Satellite data and hydrology have found answers.

To stand beside the Great Pyramid at Giza in the Eastern Sahara is to be awed, both by its immense size and the millions of huge blocks of stone from which it was constructed. The silent monument exudes ancient mystery. It’s not surprising that the precision and mastery of its construction has given rise to theories of help from extraterrestrial time-travellers. 

The oldest and largest of the three pyramids at Giza, The Great Pyramid, was built for Pharaoh Khufu 4,600 years ago and consists of around 2.3 million blocks of yellow limestone and granite weighing more than two tonnes apiece. Each side of the base measures 230 metres and its original height (before its limestone skin was scavenged) was 147 metres. Construction is estimated to have taken 23 years.

Great Pyramid

Cutaway of the Great Pyramid. (Graphic: Wiki Commons)

The puzzle has always been why most of the 30 pyramids were built many kilometres from the river, requiring complicated transport over sand to the building sites.

The blocks from which the Great Pyramid was constructed were transported down the Nile from a quarry at Thebes, hundreds of kilometres to the south.

Using radar satellite imagery in conjunction with geophysical data and deep soil coring into the sediment of the Nile Valley, a group of scientists has discovered an extinct branch of the Nile running along the foothills of the Western Desert Plateau, where most of the pyramids lie. They named it the Ahramat Branch, ahramat meaning pyramid in Arabic.

pyramids nile

A topographic impression of a segment of the former Ahramat Branch in the Nile floodplain near the Giza Plateau. The causeways of the four pyramids lead to an inlet, which we named the Giza Inlet, that connects from the west with the Ahramat Branch. These causeways connect the pyramids with valley temples which acted as river harbours in antiquity. These river segments are invisible in optical satellite imagery since they are masked by the cultivated lands of the Nile floodplain. The photo shows the valley temple of Khafre Pyramid. (Image source: Author Eman Ghoneim)

They found that many of the pyramids, dating to the Old and Middle Kingdoms, have causeways that led to the now-lost river and terminated with valley temples, which may have acted as river harbours along it. 

“We suggest that the Ahramat Branch played a role in the monuments’ construction and that it was … used as a transportation waterway for workmen and building materials to the pyramid sites,” the researchers write in the journal Nature.

In the time of pyramid construction, according to the study, Egypt was very different from what it is today. Around 12,000 years ago at the end of an ice age, the Sahara transformed from a hyper-arid desert to a savannah-like environment with large river systems and lake basins. The Nile Valley, however, was inhospitable to humans because of higher river levels and a swampy environment.

Up to about 5,000 years ago, the Nile would have had several secondary channels branching across the floodplain. However, from about that time, rainfall greatly declined and people moved out of the desert and settled along the edge of the floodplain. This coincided with the beginning of the Old Kingdom Period (2686 BCE) and the time when early pyramid complexes began to be constructed.

pyramids nile

The ancient Ahramat Branch of the Nile and the pyramids dotted along its course (Source: Esri, Maxar, Earthstar Geographics).

Most of the key Egyptian cities and monuments were then built along the Nile’s banks and its peripheral branches. Over time, according to the study, the main course of the Nile migrated eastwards and its peripheral branches silted up, leaving behind many ancient Egyptian sites distant from the present-day river course.

Until now, most of these movements have been hard to trace because on-ground searches were masked by human occupation or broad sand and silt sheets.

“Even though the largest concentration of pyramids in Egypt are located along a narrow desert strip from south Lisht to Giza, no explanation has been offered as to why these pyramid fields were condensed in this particular area,” the researchers say.

“Monumental structures, such as pyramids and temples, would logically be built near major waterways to facilitate the transportation of their construction materials and workers. Yet, no waterway had been found near the largest pyramid field in Egypt, with the Nile River lying several kilometres away.”

They used remote satellite sensing and geomorphological, soil coring and geophysical evidence to trace the long-lost ancient river branch to provide the first map of the Lisht-Giza waterway. It explains why and how the pyramids were built where they are and how the area was accessed.

“It has been speculated by many scholars that the ancient Egyptians used the Nile River for help transporting construction materials to pyramid building sites,” say the researchers. “But until now, this ancient Nile branch was not fully uncovered or mapped. 

“This work can help us better understand the former hydrological setting … and help us learn more about the environmental parameters that may have influenced the decision to build these pyramids in their current locations.”

We may know how millions of giant blocks were transported to the building sites, but by what means they were so precisely cut and stacked to form perfect pyramids has spawned many theories and few hard facts. These huge edifices and the level of knowledge and culture required to produce them remain enigmatic. Their builders may not have been extraterrestrials, but they were extraordinarily sophisticated. DM

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  • The real Ellon Must says:

    The pyramids were built along the Nile’s banks. As postulated by that great scholar Terry Pratchett in his seminal work “Pyramids” from 1989. I do hope the researchers referenced him in their paper. Also famous for the quote “Look after the dead, and the dead will look after you.”

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