• Researchers reconstructed 8,000 years of the flow of Giza floodplain
  • The waters would have been high enough when the pyramids were being built
  • The Khufu branch may have "facilitated" the transport of building materials

Experts found evidence that a "now defunct" branch of the Nile River was once high enough that it could have been used to transport the materials used to build the pyramids of Egypt, shedding light on the mystery of how the famous structures were built.

The pyramids of Egypt are among the most iconic structures in the world, with the Pyramid of Giza being one of the Seven Wonders of the Ancient World for good reason.

In fact, it is the only one out of seven that's still standing. However, exactly how they were made has remained an enigma, though experts have gathered a few pieces of evidence to solve the puzzle through the years.

In a new study, published Monday in the journal Proceedings of the National Academy of Sciences, a team of researchers had a closer look at evidence from where the Nile River once possibly flowed.

"It is now accepted that ancient Egyptian engineers exploited a former channel of the Nile to transport building materials and provisions to the Giza plateau," they wrote. "However, there is a paucity of environmental evidence regarding when, where, and how these ancient landscapes evolved."

For their work, the researchers looked at sediment samples from various sites and analyzed the "fossilized pollen grains" that may have gotten trapped in them for thousands of years, according to a feature on

Indeed, the researchers were able to reconstruct 8,000 years of the Giza floodplain, and they found that the Khufu branch of the Nile River actually had high water levels at the time when the major pyramids were being built some 4,000 years ago.

It was high enough for a long enough time "for nature to consider it permanent," noted Importantly, the water levels would have been high enough to have almost reached Giza. As such, it's possible that this branch of the Nile could have played an important role in transporting the building materials that were needed for the pyramids.

"The Khufu branch remained at a high-water level (~40% of its Holocene maximum) during the reigns of Khufu, Khafre, and Menkaure, facilitating the transportation of construction materials to the Giza Pyramid Complex," the researchers wrote, enlightening the world with how one of the most majestic and enigmatic structures of the world was built.

With the researchers' new find, the mystery of the pyramids' construction takes one step closer to being unraveled.

The pyramids of Egypt were constructed using millions and millions of large, granite and limestone blocks, some of which weighed between 25 and 80 tons. Reuters