pyramid

A pyramid is a structure or monument, usually with a quadrilateral base, which rises to a triangular point. In the popular imagination, pyramids are the three lonely structures on the Gizaplateau at the edge of the Sahara Desert but there are over seventy pyramids in Egypt stretching down the Nile River Valley and, in their time, they were the centers of greattemple complexes. Although largely associated exclusively with Egypt, the pyramid shape was first used in ancient Mesopotamia in the mud-brick structures known as ziggurats, and continued to be used by the Greeks and Romans.
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