<P> 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 . </P>
how long did it take to build the great pyramid of egypt
a 10 - to 20 - year period