Today, the famous pyramids of Giza are known as sand-colored monuments that seem to blend into the surrounding desert, but they were originally built to stand out in spectacular fashion. When the pyramids were first erected about 4,500 years ago to mark the tombs of Egyptian pharaohs, they were covered with a polished white limestone that would have sparkled in the sun and made the already-imposing structures even more dazzling.
According to ancient papyrus scrolls written by people who actually participated in the construction of the pyramids, workers transported boats filled with limestone up the Nile River to the building site in Giza. The limestone casing stones were thoroughly polished in order to increase their luster, and each one weighed upwards of 15 tons. The fact that these massive polished stones were used to encase the entirety of each pyramid, fitted together perfectly to create a nearly seamless white exterior, is a testament to the engineering genius of the ancient Egyptians. Over the centuries, most of the limestone exterior of the pyramids has been destroyed, worn away, or stripped for use in other construction projects, but faint remnants of weathered white limestone can be seen toward the top of Giza’s Pyramid of Khafre — the last remaining architectural evidence of what pyramids looked like in the days of the pharaohs.