An international panel overseeing the restoration of the Great Pyramids in Egypt overcomes years of frustration when it abandons modern construction techniques in favour of the method employed by the ancient Egyptians.
Located at Giza outside Cairo, some of the oldest manmade structures on earth were showing severe signs of decay by the early 1980s. Successful repair work began on the 4,600-year-old Sphinx in 1981, but the restoration of the pyramids proved destructive when water in modern cement caused adjacent limestone stones to split. On January 12, 1984, restorers stopped using a mortar and adopted the system of interlocking blocks practiced by the original pyramid builders. From thereon, the project proceeded smoothly.
The ancient Egyptians built nearly 100 pyramids over a millennium to serve as burial chambers for their royalty.
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