The Pyramids of Giza are among Egypt's most famous landmarks. The Great Pyramid is made up of 2.3 million stone blocks, weighing five million tonnes in total. For centuries no one has known precisely how they were built, or how the stones were transported.

Using radar satellite imagery, historical maps and geophysical surveys, a research team has mapped a long-lost, ancient branch of the River Nile - which they believe was buried by a major drought and sandstorms thousands of years ago. They think this waterway was used for the transportation of heavier blocks, equipment and people and finally explains how the Pyramids were constructed. So is this mystery finally wrapped up?

Rehab Ismail, a BBC journalist in Cairo, describes what it’s like to visit the Pyramids of Giza and explains what the Egyptian authorities are doing to preserve the area from over-tourism. Egyptologist Yossra Ibrahim tells us which mysteries have been solved and which still remain.

Archive courtesy of British Pathé.

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