how long did it take to build great pyramid of giza
Great Pyramid of Giza Based on these estimates, building the pyramid in 20 years would involve installing approximately 800 tonnes of stone every day. Additionally, since it consists of an estimated 2.3 million blocks, completing the building in 20 years would involve moving an average of more than 12 of the blocks into place each hour, day and night. The first precision measurements of the pyramid were made by Egyptologist Sir Flinders Petrie in 1880–82 and published as The Pyramids and Temples of Gizeh.[5] Almost all reports are based on his measurements. Many of the casing stones and inner chamber blocks of the Great Pyramid fit together with extremely high precision. Based on measurements taken on the northeastern casing stones, the mean opening of the joints is only 0.5 millimetre wide (1/50 of an inch).[6]
Great Pyramid of Giza Based on a mark in an interior chamber naming the work gang and a reference to the fourth dynasty Egyptian Pharaoh Khufu, Egyptologists believe that the pyramid was built as a tomb over a 10- to 20-year period concluding around 2560 BC. Initially at 146.5 metres (481 feet), the Great Pyramid was the tallest man-made structure in the world for more than 3,800 years. Originally, the Great Pyramid was covered by limestone casing stones that formed a smooth outer surface; what is seen today is the underlying core structure. Some of the casing stones that once covered the structure can still be seen around the base. There have been varying scientific and alternative theories about the Great Pyramid's construction techniques. Most accepted construction hypotheses are based on the idea that it was built by moving huge stones from a quarry and dragging and lifting them into place.