The Great Pyramid of Giza is the largest Egyptian pyramid and tomb of Fourth Dynasty pharaoh Khufu. Built in the 26th century BC during a period of around 27 years, it is the oldest of the Seven Wonders of the Ancient World, and the only one to remain largely intact. As part of the Giza pyramid complex, it borders present-day Giza in Greater Cairo, Egypt. Initially standing at 146.6 metres (481 feet), the Great Pyramid was the tallest man-made structure in the world for more than 3,800 years. Over time, most of the smooth white limestone casing was removed, which lowered the pyramid's height to the present 138.5 metres (454.4 ft). What is seen today is the underlying core structure. The base was measured to be about 230.3 metres (755.6 ft) square, giving a volume of roughly 2.6 million cubic metres (92 million cubic feet), which includes an internal hillock.
