The Changing Nile and How the Pyramids were Built

How the pyramids were built: Painting of the pyramids from 1839. Courtesy Photo Companion to the Bible.

Could a better understanding of the Nile River help explain how the pyramids were built? The pyramids of Giza are some of the most recognizable monuments of all time, yet the finer details of their construction are still debated. Now, a study in the Proceedings of the National Academy of Sciences proposes to have solved one of the biggest remaining questions: How did the ancient builders manage to transport the enormous mass of material to the construction site? Although long since dried up, a large branch of the Nile River apparently passed by the foot of the Giza Plateau during the Old Kingdom period (c. 2663–2181 B.C.E.). This allowed the Egyptians to transport construction materials and equipment up to the future site of the pyramids, claims the new study.

Constructing a Pyramid with Egypt’s Disappearing River

One of the biggest mysteries about how the pyramids were built, is how the Egyptians were able to move the millions of the two-ton limestone blocks that they needed for the construction. While one of the leading theories is that the Egyptians harnessed the Nile to their aid, the modern Nile sits miles away from Giza. But that was not always the case, and during the Old Kingdom, a long-lost branch of the Nile allowed easy access to the Giza Plateau.

Model of Giza pyramid complex, showing a possible branch of the Nile. Courtesy Photo Companion to the Bible.

Using sediment cores, in conjunction with recent archaeological finds and ancient texts, an international team was able to identify and model the water level over the past 8,000 years for a bygone branch of the Nile River. The flow of the branch – dubbed the Khufu branch after the pharaoh who built the first of the great pyramids – steadily declined throughout the Old Kingdom and disappeared by the time of Alexander the Great (r. 332–323 B.C.E.).

However, during the first half of the Old Kingdom, when the pyramids were built, the flow of the Khufu branch was high enough to operate as a highway across the desert, connecting the Giza Plateau to sources of limestone and other resources needed for the construction of the pyramids. “It was impossible to build the pyramids here without this branch of the Nile,” Hader Sheisha, an author of the study, told New York Times.

The modern Nile sits miles away from Giza. Courtesy Photo Companion to the Bible.

This is not merely a theory based on later archaeological analysis, though. The theory is backed up by a recently discovered collection of papyri, dating back to the time of Pharaoh Khufu (r. 2589–2566 B.C.E.). The papyri – discovered in 2013 at an ancient Egyptian port on the Red Sea – mention a harbor near Khufu’s pyramid known as the “Entrance to the Lake of Khufu.” Other papyri mention the use of boats to take limestone from the site of Toura, 10 miles from Giza, to the harbor complex. Matching these ancient texts to the recent archaeological reconstructions of the water system during the Old Kingdom appears to have unlocked the mystery of how the pyramids were built. According to the team, the results of their study might also aid in understanding the possible water systems surrounding the earlier pyramid complexes at Saqqara and Dahshur, south of Giza.

Aerial photograph of the Giza pyramids. Courtesy Photo Companion to the Bible.

Although the Khufu branch of the Nile River was large enough to enable the construction of the great pyramids of Giza, its gradual decline over the next 2000 years – along with shifting burial practices – would likely be a contributing factor to the end of the age of pyramids.