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Egypt’s Biggest Pyramid Isn’t Quite Square at Its Base

But the ancient builders got pretty close.

(Photo: Nina/CC BY-SA 3.0)

The Great Pyramid of Giza, the largest of three pyramids built more than 4,000 years ago in Egypt, is 455 feet tall, and 756 feet wide at its base.

But one scientist recently discovered that the base, which appears to be square, isn’t quite as perfect as it looks, according to Live Science, which is significant in part because it helps suggest how ancient Egyptians built the pyramids given the tools of the time.

To make the latest measurements, scientists first searched to find the original edges of the pyramid, which have eroded over the years. They then plotted, using a statistical analysis, the true length of the east and west sides of the pyramid’s original base, finding that the west was around 5.55 inches longer than the east.

Coming up short by so little on a project of this scale is impressive, Glen Dash, one of the scientists who calculated the number said, and he thinks it also shows that the pyramid was built with a grid as a sort of blueprint.

That’s because the pyramid’s positional axis is also off by tiny, but similar amounts. However you measure it, though, Dash said the Egyptians’ achievement remains what it was in ancient times: a wonder of the world.

“We hope to eventually figure out how the Egyptians laid out the pyramid with such precision and, in doing so, hope to learn much about the tools and technology they had at their disposal,” Dash said, according to Live Science.