PHYS.ORG = Some 31 pyramids in Egypt, including the Giza pyramid complex, may originally have been built along a 64-km-long branch of the river Nile which has long since been buried beneath farmland and desert. The findings, reported in a paper in Communications Earth & Environment, could explain why these pyramids are concentrated in what is now a narrow, inhospitable desert strip. The Egyptian pyramid fields between Giza and Lisht, built over a nearly 1,000-year period starting approximately 4,700 years ago, now sit on the edge of the inhospitable Western Desert, part of the Sahara. Sedimentary evidence suggests that the Nile used to have a much higher discharge, with the river splitting into several branches in places.
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