Giza Pyramids (Egypt)

The great pyramids, whose precision and stellar alignment fuel ancient-astronaut theory.

The Great Pyramid of Giza is the largest of the Egyptian pyramids and the most famous landmark of the Giza pyramid complex in Giza, Egypt. It is the oldest of the Seven Wonders of the Ancient World, and the only wonder that has remained largely intact. The Great Pyramid served as the tomb of Egyptian Pharaoh Khufu ("Cheops"), who ruled during the Fourth Dynasty of the Old Kingdom. It was built c. 2600 BC over a period of about 26 years. Initially standing at 146.6 metres (481 feet), the Great Pyramid was the world's tallest human-made structure for more than 3,700 years. Over time, most of the smooth white limestone casing was removed, which lowered the pyramid's height to the current 138.5 metres (454.4 ft); what is seen today is the underlying core structure. Each side of the base was measured to be about 230.3 metres (755.6 ft) in length, giving a volume of roughly 2.6 million cubic metres (92 million cubic feet), which includes an internal hillock. The dimensions of the pyramid were 280 royal cubits (146.7 m; 481.4 ft) high, a base length of 440 cubits (230.6 m; 756.4 ft), with a seked of ⁠5+1/2⁠ palms (a slope of 51°50'40"). The Great Pyramid was built by quarrying an estimated 2.3 million large blocks, weighing 6 million tonnes in total. The majority of the stones are not uniform in size or shape, and are only roughly dressed. The outside layers were bound together by mortar, primarily local limestone from the Giza Plateau was used for its construction.