The Great Pyramid of Giza (also known as the Pyramid of Khufu) is only extant structure that stands tall among the seven ancient wonders of the world. In fact this incredible architectural feat was accomplished in around 2560 BC, and held the record for the world’s tallest structure for a whopping 3,800 years with its then-impressive height of 481 ft (146.5 m). Now we use the term ‘incredible’ because of the numbers game involved in the ancient scope. To that end, the monumental giant has a base area of around 570,000 sq ft (equivalent to almost 10 American football fields), and a humongous volume of 88 million cubic ft (or 2.5 million cubic m) that accounts for an extraordinary 5.9 million tons of mass. This gargantuan scope was achieved by the use of 2.3 million stone blocks (ranging from 2 to 30 tons) – that comes to an average of 800 tons of stones being installed each day, with 12 stones being precisely placed every hour! Some of these stones (especially, the ones used in the inner chambers) weigh more than 50 tons, and yet they were transported to the site from Aswan, which is 800 km away.
Suffice it to say, this was an impressive feat, given the lack of modern infrastructural facilities in ancient Egypt. But unfortunately, beyond mind-boggling numbers, historians are still divided on how the Great Pyramid was actually built. Now harking back to actual historical theories and hypotheses, the earliest known theory was probably put forth by Herodotus when he possibly visited the Pyramids in 450 BC. He simply mentioned the use of ‘machines’ for achievement of leviathan engineering tasks, like the lifting of stones. These machines can be presumably associated with crane-like devices (more specifically the Egyptian shadouf). Almost three hundred years later, Diodorus of Sicily provided an arguably more comprehensive conjecture that talked about the use of mounds (or ramps). This theory basically entailed the scenario where (makeshift) ramps were raised alongside the pyramid, thus allowing the workers to access and the built the rising levels of the structure.
Now it should be noted that most historians and archaeologists tend to favor either of these two theories. But a fascinating new theory had surfaced in the academic world (by 2007), and it encompasses a scenario where an internal ramp system was utilized for building the top two-thirds of the Great Pyramid (while an external ramp was used for setting up the lower parts). This incredible hypothesis was put forth by Jean-Pierre Houdin, a French architect who developed an earlier theory suggested by his father (a retired civil engineer) that involved the use of an internal system.
By 2005, Houdin collaborated with Dassault Systemes, and together they devised a 3D animation of the theory, partly powered by software applications such as CATIA. Quite interestingly, this 3D medium morphed in an educational scope with an interactive guide. Bob Brier, a senior research fellow at the Long Island University, and a contributing editor to Archaeology magazine (published by Archaeological Institute of America), endorsed the hypothesis, and his nifty article provides some great insights into the credible theory.
The animated documentary presented below gives a fascinating overview of the conjectural internal ramp process that might have been used to build the Great Pyramid. The video was created by Dassault Systemes as a part of the Khufu Reborn project.