The ancient Greeks considered the Great Pyramid one of the seven wonders of the world and, unlike the other six, it has survived relatively intact despite the loss of almost all of its white limestone casing.
The sheer scale of the pyramid never fails to astonish and the statistics are awesome. It is 146.59 metres high and the sides are 230.33 metres long at the base; it has a volume estimated at 2.6 million cubic metres. A recent analysis suggests it may originally have contained about four million limestone blocks. The larger core blocks at the base are estimated to weigh up to 15 tonnes each while the granite blocks used for the roof of the burial chamber are estimated to weigh up to 80 tonnes and were quarried in Aswan and transported 700 miles to Giza by boat before being hauled up to the plateau and placed in position nearly 50 metres above ground. It took a just over 20 years to build and before Khufu was cold in his grave the workforce was moved a few miles up the Nile to Abu Roash to start work on a pyramid for his successor. Khufu's pyramid and four others of a similar scale were built in a century, along with a handful of smaller pyramids and a few which were never finished.
Despite claims from non-mainstream authors of extra-terrestrial involvement or advanced technical knowledge which has since been lost, Egyptologists agree that this feat was achieved through careful organisation and the ability to mobilise and maintain a workforce of about 20,000 Egyptians who spent months dragging blocks of stone around the Giza plateau.
American Egyptologist Mark Lehner has excavated a site to the south-east of the Giza pyramids and has found evidence of large-scale food production related to the pyramid complex of Menkaure who built the smallest of the three Giza pyramids. Meanwhile, Zahi Hawass has investigated the tombs of the workforce who built the pyramids. Both these projects tell us much about the human dimension of pyramid construction.
While the technological achievements of the ancient Egyptians in constructing such enormous and enduring monuments has long been recognised, there are some astonishing aspects of pyramid construction which have only been revealed through moderntechnology. Repeated surveying of the pyramids with ever more accurate equipment over the past century or so has revealed the amazing precision achieved by the ancient surveyors.
In the case of the Great Pyramid, the 921 metres of pyramid base are levelled to within 2.1 centimetres, while the deviation of the alignment of the sides from true North is only about 1Z20th of a degree. Although it is agreed that the Egyptians were working with simple tools, we have no concrete evidence as to how such precision was achieved and specialists still debate the issue.
Despite problems of evaporation, it is likely that water was used in some way for levelling, while most researchers favour stellar methods of orientation.
Computer programs are available which use data collected by NASA to model the position of the sun and stars at any point in antiquity and these are invaluable for visualising how the night sky looked when the pyramids were built.
The Complete Pyramids
By Mark Lehner Thames and Hudson, pound;24.95
By Miroslav Verner Atlantic Books, pound;25