Engineers have a new theory on how Egypt's first pyramid was built

Transcript

LEILA FADEL, HOST:

Scholars think they have an answer to a question that has puzzled generations. How did ancient Egyptians, thousands of years ago, move all those heavy stones, stack them up and make the pyramids?

STEVE INSKEEP, HOST:

A recent study examined Egypt's oldest monumental pyramid, which is called the Step Pyramid of Djoser. It's more than 200 feet tall, and the researchers found evidence that Egyptians used the power of water to help to build it. The lead author of this study is Xavier Landreau.

XAVIER LANDREAU: The water would have been guided to, like, a central shaft that is located just beneath the pyramid that is 28 meters deep, and through filling and draining cycle, this shaft would have raised the float carrying stones.

FADEL: So this pyramid would have been like a volcano, but with building materials floating up the center.

INSKEEP: Yeah, the water did the work. Landreau and his team had originally set out to map the area near the pyramid.

FADEL: And they pursued different theories about what this monument was originally supposed to be for.

LANDREAU: One of the very first was it could be a cattle pen. A second was it could be a fortress to protect against attacks. A third one was a celebratory arena for the Pharaoh, and the last one was, like, a funerary enclosure.

INSKEEP: Whatever its purpose, the researchers now think that a hydraulic lift floated the stones up to the higher reaches of that structure.

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