Antiquity History

Article · Ancient Egypt

The Great Pyramid of Giza: Construction Theories

The Great Pyramid of Giza, the tomb of the pharaoh Khufu of the Fourth Dynasty, is the largest pyramid ever built, the only one of the Seven Wonders of the Ancient World still standing, and the most massive stone building in the ancient world. Built around 2580–2560 BCE, the pyramid was originally 146.6 meters (481 feet) high and 230.3 meters (756 feet) along each side, with a volume of about 2.6 million cubic meters. Its construction has been the subject of intense archaeological research, engineering analysis, and (in the popular imagination) a great deal of romantic speculation. The modern consensus is that the pyramid was built by a state-organized workforce of about 100,000 skilled and unskilled laborers, who cut the stones with copper and dolerite tools, transported them by sledges on slipways, and raised them into position by a combination of ramps, levers, and counterweights.

This page is a complete guide to the construction of the Great Pyramid. It explains the historical context, the engineering, and the modern theories. It links back to the Pyramids of Giza cluster, the Sphinx of Giza page, and the Egyptian Pharaohs cluster.

The Pyramid in Context

The Great Pyramid was the culmination of a long tradition of pyramid building in ancient Egypt. The earliest known Egyptian pyramid, the Step Pyramid of Djoser at Saqqara, was built by the architect Imhotep in the Twenty-Seventh Century BCE. The Step Pyramid was a series of six mastaba-like structures stacked on top of each other. The “true” smooth-sided pyramid was developed in the Fourth Dynasty, beginning with the pyramid of Meidum and the three pyramids at Dahshur, before reaching its highest point at Giza.

The Great Pyramid was built by the pharaoh Khufu (in Greek, Cheops) of the Fourth Dynasty, who ruled from about 2589 to 2566 BCE. Khufu was the son of Sneferu, the founder of the Fourth Dynasty, and the father of Djedefre and Khafre. He is mentioned in the famous Westcar Papyrus, in which his court magician tells him stories of the great magicians of the past, and he is named (with his sons) in the inventory of the diorite statue of Hemiunu, the architect of the Great Pyramid.

The Stones

The Great Pyramid is built of about 2.3 million blocks of stone, averaging about 2.5 tons each. The core blocks are made of local limestone, quarried from the Giza plateau itself. The fine white casing stones are Tura limestone, quarried on the east bank of the Nile and ferried across the river. The granite blocks of the King’s Chamber and the relieving chambers above it came from Aswan, more than 800 km (500 miles) up the Nile.

The stones were cut with copper chisels and dolerite hammer stones. Copper is a soft metal, and the cutting rate was slow — about 0.5 cm (0.2 inches) per cut. Modern experiments have shown that a crew of about 10–12 men could cut a 2.5-ton block in about 10–12 days. The stones were then shaped and polished with copper tools and abrasive sand.

The Transportation

The transportation of the stones was one of the great logistical achievements of the ancient world. The stones were transported from the quarries to the Giza plateau by sledges on slipways. The famous 2014 experiment by the Egyptian engineer Yannis Galanides and his team, published in Physical Review Letters, showed that wetting the sand in front of the sledge with water reduced the friction by about 50%, allowing a small crew of men to drag a heavy block. (A team of about 50 men could drag a 2.5-ton block on a wet sandy slipway.)

The granite blocks of the King’s Chamber, which came from Aswan, were transported on specially built barges. The blocks were ferried down the Nile to Giza, and they were then dragged to the construction site on the same kind of sledges. The largest of the granite blocks, the slabs that form the ceiling of the King’s Chamber, weigh about 80 tons, and they are among the heaviest stones ever moved by ancient Egyptians.

The Construction

The construction of the Great Pyramid is one of the great engineering puzzles of the ancient world. The main questions are: how were the stones raised into position, and how were they fitted so precisely that the joints between them are too tight to admit a knife blade.

The traditional theory, that a long, single ramp ran from the quarry up one side of the pyramid, has been largely rejected by modern scholars. A ramp of the necessary size would have required more material than the pyramid itself, and it would have had to be dismantled and rebuilt as the pyramid rose.

The most widely accepted modern theories are:

The Interior of the Pyramid

The Great Pyramid contains three main chambers: the King’s Chamber, the Queen’s Chamber, and an unfinished chamber carved into the bedrock beneath the pyramid. The chambers are connected by a series of passages, including the Grand Gallery, a corbelled passage 8.6 meters (28 feet) high that leads up to the King’s Chamber.

The King’s Chamber is the only chamber finished with a high, corbelled ceiling. It is built of enormous red granite blocks, with a ceiling made of nine granite slabs weighing about 70 tons each. Above the King’s Chamber are five Relieving Chambers, designed to redistribute the weight of the stone above and to prevent the ceiling from collapsing. The existence of the Relieving Chambers was discovered in 1837 by the British general Howard Vyse, who blasted his way into the upper part of the pyramid.

The Pyramidion

The pyramidion, the capstone of the pyramid, was a single piece of stone, probably granite, that was placed on the top of the pyramid when the construction was complete. The original pyramidion of the Great Pyramid is missing, but pyramidions of other pyramids survive. They were often inscribed with the name of the pharaoh and the names of the gods, and they were usually covered in gold leaf or electrum.

The Meaning of the Pyramid

The Great Pyramid was a royal tomb, and the pharaoh was buried deep inside the structure. The pyramid was a kind of solar ladder, a stairway by which the dead pharaoh’s soul could climb to join the sun god Ra in the heavens. The pyramid’s smooth, sloping sides may have been meant to imitate the rays of the sun falling on the earth.

The pyramid was also a political statement. It was the largest building in the world at the time of its construction, and it was visible for miles in every direction. It was a demonstration of the power of the pharaoh, the organization of the Egyptian state, and the technical skills of the Egyptian craftsmen. The pyramid was, quite simply, the most ambitious building project in the ancient world, and it was the model for all the pyramids that came after.

The Legacy of the Great Pyramid

The Great Pyramid has been the subject of intense study since antiquity. Herodotus, the Greek historian, visited Giza in the fifth century BCE and wrote a detailed account of the pyramid and its construction. The medieval Arab historians preserved many of the ancient stories. The Napoleonic expedition of 1798 produced the first modern descriptions and measurements. The modern archaeological expeditions of the late 19th and 20th centuries have produced a much more detailed picture of the construction.

The Great Pyramid is one of the most recognizable monuments in the world, and it has been the subject of countless works of art, literature, and science fiction. It has been the focus of the alternative archaeology movement, which claims that the pyramid was built by an unknown advanced civilization or by extraterrestrials. The mainstream archaeological and engineering consensus, however, is that the pyramid was built by a large, well-organized workforce of skilled and unskilled laborers, using the tools and techniques of the Old Kingdom.