MYS0CSMNN502D05·Mystery · site

How the Great Pyramid was built

Nina · CC BY 2.5

Where: Giza plateau, Egypt⁠[11]
Built for: Khufu, Fourth Dynasty⁠[5]
When: about 2600–2550 BC; Old Kingdom start modelled at 2691–2625 BC⁠[2]
Size: about 230 m base, 146.6 m original height⁠[1]
Workforce: about 20,000 to 25,000 at a time, rotating⁠[11]
Key document: Papyrus Jarf A and B, the Diary of Merer, Year 26 of Khufu⁠[5]
Status: Partly explained
Questions: 3 of 5 answered

People KhufuKing of the Fourth Dynasty · 26th century BC MererInspector leading a boat crew · fl. Year 26 of Khufu AnkhhafVizier, director of Ro-She Khufu Mark LehnerDirector, Ancient Egypt Research Associates Pierre TalletEgyptologist, Sorbonne; director of the Wadi al-Jarf excavation

All 6 people ›

Zahi HawassEgyptologist; excavator of the builders' cemetery

Catalog keyMYS0CSMNN502D05

The Great Pyramid is the tomb of Khufu, second king of the Fourth Dynasty, on the Giza plateau west of Cairo. Its base is about 230 m on each side and it originally stood 146.6 m high, faced with fine white limestone from the Tura quarries across the river and built on a core of local limestone, with granite from Aswan in the burial chamber⁠[1]. Bayesian modelling of radiocarbon dates places the start of the Old Kingdom at 2691–2625 BC and Khufu's reign in the 26th century BC⁠[2].

The question of who built it was answered by excavation. South of the plateau, Mark Lehner's team has dug a walled settlement of galleries, bakeries, breweries and storerooms that housed and fed a rotating labour force⁠[3]; west of it Zahi Hawass found the builders' cemetery, with the titles of overseers and gangs⁠[4]. In 2013 Pierre Tallet's team found at Wadi al-Jarf on the Red Sea the oldest inscribed papyri known: the logbooks of Inspector Merer, whose crew of about forty men ferried Tura limestone to Akhet-Khufu, "Horizon of Khufu", the pyramid itself, in the year after the 13th census, Year 26 and the last known year of the reign, under the vizier Ankhhaf⁠[5]⁠[6].

What the evidence does not yet fix is the method on site. No ramp survives at the Great Pyramid, and the rival reconstructions, a straight ramp, a spiral ramp, an internal ramp, or lifting with levers, each fit some of the physical traces and none has been shown⁠[1]. Since 2017 muon imaging has found two previously unknown spaces inside the pyramid, a corridor behind the north face, since viewed by endoscope, and a void at least 30 m long above the Grand Gallery that has not been entered⁠[7]⁠[8]. Of the 5 questions on this site, 3 are answered. The most likely answer to “How were the blocks raised onto the pyramid?”, not yet confirmed: shorter, steeper ramps were used with post-and-rope haulage of the kind excavated at Hatnub, combined with….

Key questionsset by the editors

How were the blocks raised onto the pyramid?Most likely: shorter, steeper ramps were used with post-and-rope haulage of the kind excavated at Hatnub, combined with…

What is the Big Void above the Grand Gallery?No answer ahead yet

Who built the Great Pyramid, and how was the work organised?Answered: a rotating, provisioned Egyptian workforce of about 20,000 to 25,000 under royal officials built it during…

All 5 questions

The site

The pyramid stands on a levelled outcrop of the Mokattam limestone, with the core blocks quarried from a pit 300 m to the south, whose cut faces and the dolerite pounders and copper tools in them show the method⁠[1]. Casing stone came by boat from Tura, granite from Aswan 800 km upstream, and gypsum mortar from the Fayum⁠[6]⁠[1]. Pollen cores at Giza reconstruct a Khufu branch of the Nile running close to the plateau with high water in the Fourth Dynasty, so cargo boats could reach a harbour basin at the foot of the causeway⁠[9]. Satellite radar and coring trace a former 64 km branch, named Ahramat by the authors, along which 31 pyramids of the Old and Middle Kingdoms were built with their causeways ending on its bank⁠[10].

Tombs of the pyramid builders, including the tomb of PetetyAhmed Yousry Mahfouz. CC BY-SA 4.0Artifact

The settlement called Heit el-Ghurab, "Wall of the Crow", lies 400 m south-east of the Sphinx: long galleries read as barracks for rotating gangs, bakeries with bread moulds in bulk, a copper workshop, and an administrative building with silos; its sealings date it mainly to Khafre and Menkaure, the kings after Khufu, with Khufu's own town presumed to lie beneath the modern village⁠[3]⁠[11]. The cemetery on the escarpment above holds mudbrick tombs with titles such as "overseer of the side of the pyramid" and "director of the workers", and skeletons with set fractures⁠[4].

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Site Region

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Great Pyramid of GizaPyramid

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Pyramid of KhafrePyramid

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Pyramid of MenkaurePyramid

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Heit el-Ghurab workers' townSettlement site

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MappedWithin 1 kmBase map © OpenStreetMap contributors

Timeline

Timeline

Squeezed where little happened. Each mark is a published claim, by how it stands:AcceptedMost likelyStill possibleDisputedRuled out

What was found

The Merer papyri are day-by-day accounts. The crew loads stone at Tura, sails to the pyramid, unloads at a basin called She-Khufu under the control of Ro-She Khufu, which Ankhhaf directs, and returns, with a round trip of two to three days and the voyages running through roughly July to November⁠[5]⁠[6]. The same crew worked at the Red Sea harbour, whose galleries, jetty and anchors show a state able to run long-distance supply chains for copper and turquoise from Sinai⁠[12]⁠[13].

The faunal remains from the settlement show cattle, sheep and goat brought in on the hoof in quantities that imply provisioning from across the country, and the bakeries show bread production on an industrial scale⁠[14]⁠[11]. The workers were buried with grave goods and received medical care; the cemetery contradicts the Herodotean picture of slave labour⁠[4].

At Hatnub, the alabaster quarry 300 km south, the Anglo-French mission excavated a haulage ramp of Khufu's reign: a central ramp flanked by two staircases with post holes, read as anchors for posts around which ropes were run so that a sled could be hauled up a slope of 20 per cent or more⁠[15]⁠[16]. It is the only Old Kingdom ramp of this type yet excavated and shows one steep-slope method that was in use.

North Face Corridor: muon images and endoscope viewsProcureur et al., 2023. CC BY 4.0Artifact

Inside the pyramid, the ScanPyramids mission's nuclear emulsion, scintillator and gas detectors found in 2017 a void at least 30 m long with a cross-section like the Grand Gallery's, above it⁠[7]. A second anomaly behind the chevrons over the north entrance was measured as a corridor about 9 m long and 2 m wide with a flat ceiling, confirmed by radar and ultrasound and then seen by an endoscope in March 2023⁠[8]⁠[17]⁠[18].

What is known

The builders were Egyptians organised in gangs and phyles under named officials, paid in bread, beer and meat, working in rotation; the names, the titles, the rations and the logistics are documented⁠[5]⁠[4]⁠[11]. Lehner estimates a peak workforce of about 20,000 to 25,000, with a few thousand skilled masons employed year-round⁠[11].

First page of Quarry marks of work gangs naming Khufu in the relieving chambers — Quarry marks of work gangs naming Khufu in the relieving chambersRichard William Howard-Vyse and John Shae Perring, 1837. Public domainArtifact

The date is fixed to Khufu's reign by the papyri, by the quarry marks of work gangs naming Khufu inside the relieving chambers, and by radiocarbon. The 1984 and 1995 campaigns dated 454 samples of charcoal and plant matter from the mortar of the pyramids; the results for the Great Pyramid run 100 to 200 years older than the historical date, which the authors attribute to old wood and reused fuel rather than to an earlier construction⁠[19]. The Oxford model on short-lived samples agrees with the historical chronology to within a few decades⁠[2].

The tools and methods are those of the Old Kingdom: copper saws and chisels with sand abrasive, dolerite pounders, wooden sledges, levers, and water-borne transport, all attested by finds, quarry faces and depictions⁠[1]. Surviving ramp remains at other pyramids (Meidum, Lisht, Sinki) show both straight and wrap-around ramps were used in the period, but none survives at Giza⁠[1].

The two new spaces are real. The corridor is confirmed by three independent methods and by direct viewing⁠[18]. The Big Void is confirmed by three muon techniques but has not been imaged at resolution or entered; its purpose is unknown, and the authors proposed none⁠[7]⁠[20]. In 2025 the same team reported two air-filled anomalies behind the granite casing on the east face of Menkaure's pyramid⁠[21].

The explanations

On the raising of the blocks, four readings compete. A single straight ramp from the quarry, extended as the pyramid rose, is the oldest reconstruction; it fits the quarry's position but would have needed a volume of fill comparable to the pyramid itself by the upper courses⁠[1]. A ramp spiralling up the faces uses less material but would hide the corners that the surveyors needed to keep the faces true, and leaves no trace on the casing⁠[1]. Jean-Pierre Houdin's internal ramp, a corridor rising within the outer part of the pyramid, was proposed to explain how the upper third was built; the 2017 Big Void was greeted by some as support, but the void does not match the ramp's predicted geometry and the authors did not endorse the link⁠[7]. Lifting with levers and cribbing, as Herodotus described, is feasible for small blocks and the top courses but not shown for the whole⁠[1]. The Hatnub ramp shows that steep ramps with post-and-rope haulage were in use for heavy loads in Khufu's reign and makes shorter, steeper ramps at Giza more credible, but it was built for a quarry, not a pyramid⁠[15].

On the voids, the readings are a construction feature such as a relieving space or an access gallery left from building, a sealed chamber, or an unfinished passage; nothing yet published chooses among them⁠[8]⁠[20].

Claims that the pyramid is far older than Khufu, or was built by a lost civilisation or by visitors from elsewhere, make predictions the evidence contradicts: the papyri, the gang marks, the settlement, the cemetery and the radiocarbon all point to the Fourth Dynasty, and the stone shows the marks of copper and stone tools⁠[5]⁠[19]⁠[1]. A 2025 claim of a city 2,000 feet below Khafre's pyramid, from a radar analysis presented at a press conference, was rejected by radar specialists and by the Egyptian antiquities authority because the method cannot penetrate to such depths and no study was published⁠[22].

Published claims

Published claims and their status

Year	Who	Claimed	Status	Reason
-429	Herodotus⁠[23]	Cheops forced all Egyptians to work for him, 100,000 men at a time relieved every three months, and the pyramid took twenty years.	Disputed	The workers did serve in rotation, but excavation shows a paid, provisioned force of perhaps 20,000 to 25,000, not 100,000 under oppression⁠[11]⁠[4].
1840	Richard Howard-Vyse⁠[24]	Painted quarry marks naming Khufu inside the relieving chambers above the King's Chamber show the pyramid was his.	Accepted	The Merer logbooks independently name the pyramid Akhet-Khufu and record stone delivered to it⁠[5].
1864	Charles Piazzi Smyth⁠[26]	The pyramid was built to a divinely given 'pyramid inch' and its dimensions encode the size of the earth.	Ruled out	Petrie's survey found that the measurements Smyth relied on were wrong and do not support the pyramid inch⁠[25].
1883	W. M. Flinders Petrie⁠[25]	A triangulation survey of the pyramid gives dimensions that do not fit Smyth's pyramid inch or its prophecies.	Accepted	Petrie's figures remain a standard reference for the building's dimensions and have not been overturned⁠[1].
2001	Georges Bonani, Herbert Haas, Zahi Hawass and colleagues⁠[19]	Radiocarbon dates on mortar run 100 to 200 years older than the historical date because the builders burned old wood, not because the pyramid is older.	Most likely	A model built on short-lived samples agrees with the historical chronology to within a few decades⁠[2].
2002	Mark Lehner⁠[3]	The walled settlement south of the plateau, with galleries, bakeries and storerooms, housed and fed a rotating workforce of pyramid builders.	Accepted	The builders' cemetery and the Merer papyri show the same organised, provisioned workforce⁠[4]⁠[5].
2004	Zahi Hawass⁠[4]	The builders were buried near the pyramids with their titles and treated for injuries, so they were not slaves.	Accepted	It agrees with the settlement's rations and the logbooks' named crews and officials⁠[11]⁠[5].
2006	Jean-Pierre Houdin⁠[27]	An external ramp built the lower third and an internal spiral ramp inside the outer pyramid carried the blocks above it.	Disputed	No internal ramp has been found, and the void found by muon imaging in 2017 does not match the ramp's predicted geometry⁠[7].
2010	Christopher Bronk Ramsey and colleagues⁠[2]	Bayesian modelling of radiocarbon dates on short-lived samples puts Khufu's reign in the 26th century BC, in line with the historical chronology.	Accepted	It agrees with the regnal date of the Merer logbooks and the gang marks naming Khufu⁠[5]⁠[24].
2017	Pierre Tallet⁠[5]	Inspector Merer's logbooks record a crew of about forty ferrying Tura limestone by boat to the Great Pyramid in Year 26 of Khufu.	Accepted	The harbour excavations at Wadi al-Jarf and pollen cores showing a navigable Nile branch at Giza agree with the logbooks⁠[13]⁠[9].
2017	Kunihiro Morishima and the ScanPyramids team⁠[7]	Three muon techniques detect a void at least 30 m long above the Grand Gallery.	Accepted	Its existence rests on three independent detectors, but it has not been imaged at resolution or entered, and its purpose is unknown⁠[20].
2020	Yannis Gourdon, Roland Enmarch and Olivier Lavigne⁠[15]	A steep ramp with staircases and post holes at the Hatnub quarry, dated to Khufu's reign, shows how heavy blocks could be hauled up short, steep slopes.	Most likely	It shows the technique existed in Khufu's reign, but at a quarry, and no ramp survives at Giza to show it was used there⁠[1].
2022	Hader Sheisha and colleagues⁠[9]	Pollen cores show a Khufu branch of the Nile with high water in the Fourth Dynasty, which brought boats to the foot of the plateau.	Most likely	It agrees with the logbooks' boats delivering stone to the pyramid and with the wider former branch traced in 2024⁠[5]⁠[10].
2023	Sébastien Procureur and the ScanPyramids team⁠[8]	A corridor about 9 m long lies behind the chevrons above the north entrance.	Accepted	Radar, ultrasound and an endoscope camera confirmed it independently⁠[17]⁠[18].
2024	Eman Ghoneim and colleagues⁠[10]	A 64 km former branch of the Nile ran along the pyramid fields, and 31 pyramids' causeways end at its bank.	Most likely	It agrees with the Giza pollen cores, but the branch's course is traced mainly from satellite radar with few cores⁠[9].

What would settle it

The ramp question would be settled by physical remains: ramp foundations, post holes or debris lines on the plateau around the pyramid, which excavation of the quarry edges and the areas under later tombs could find⁠[1]. The full publication of the Wadi al-Jarf papyri, of which three volumes have appeared, and any further logbooks naming the pyramid works, would add detail on the schedule and the labour⁠[5]. Khufu's own workers' town, if it lies under the modern village, would date the provisioning system to his reign rather than his successors'⁠[11].

The Big Void would be settled by high-resolution imaging from inside the Grand Gallery and then by a minimally invasive camera, the route the North Face Corridor has already taken⁠[18].