How did ancient Egyptians stack those heavy stones of the oldest pyramid?
![How did ancient Egyptians stack those heavy stones of the oldest pyramid?](https://ic-cdn.flipboard.com/cnn.com/395cfc44a1ae4adb0cd1a69a4a757bae7ba39134/_large.jpeg)
CNN — For years, Egyptologists have hotly debated how the massive pyramids of ancient Egypt were built more than 4,000 years ago. Now, a team of engineers and geologists brings a new theory to the table — a hydraulic lift device that would have floated the heavy stones up through the middle of …