New insight into ancient civilisation
The Great Pyramid of Khufu is one of the Seven Wonders of the Ancient World, and it is a wonder how this magnificent pyramid was built.
The pyramid is formed by 2.3 million blocks of stone, and has lost little of its original height of 146 metres and 230-metre width.
So how was such an impressive pyramid built 4,500 years ago?
Clues to who built the Great Pyramid and the two Giza pyramids have been found by the University of Chicago/Harvard University Giza Plateau Mapping Project, led by archaeologist Mark Lehner.
At Giza, a vast complex that could have housed as many as 20,000 people has been discovered, as have one metre-wide mud ramps, believed to be bed platforms. Mr Lehner believes these were sleeping quarters for 2,000 people at a time.
Also in this complex are the oldest-known bakeries from ancient Egypt, Egypt's oldest paved streets and hall of columns which Mr Lehner believes was used as a communal dining hall.
Another discovery is of a separate town that may have housed a more permanent workforce, which reinforces the idea that ancient Egyptians utilised both a temporary and permanent workforce to complete massive building projects.
Much of the evidence suggests the complex belonged to kings, Mr Lehner says, so his next task is to determine whether it contained a Pharaoh's palace.
An even greater mystery is the motivation behind building these enormous man-made mountains, now known as pyramids. 'That's the real mystery,' he said.
The new discoveries will be featured in 'Egypt: Secret Chambers Revealed' on September 17 at 8am on the National Geographic Channel