Egyptologists propose that the Great Pyramid of Giza, assigned by graffiti found inside the Kings chamber to Khufu (Cheops), was built in 23[i] years and dated to 2589-2566 BC[ii] , but radio-carbon dating of the pyramid’s mortar and objects found within it, suggest the 7th wonder of the world was built between 1300 – 440 years earlier.
Radio-carbon dates collected in three separate studies[iii] suggest that the Great Pyramid was most likely built at least 400 years earlier than is currently accepted, this is based on the average of the calibrated carbon 14 dates. These results collected over a period of more than 30 years have been analysed away by Egyptologists because they do not fit the current chronological model for ancient Egypt[iv] . But the latest (2020) set of dates (3341-3094 BC)[v] confirm the earlier studies of the 80’s and 90’s, that current dating of the old Kingdom seems to be out by 400 years or more.
Two scenarios are explored to make sense of these dates:
The great pyramid was built by Khufu 400 plus years earlier, thus pushing old kingdom dates back by 400 plus years.
The great Pyramid wasn’t built by Khufu, but by some earlier unknown ruler and later adopted by and refurbished or completed by him.
Khufu and the Conventional Dates The currently accepted history of the Great Pyramid is that it was built for Khufu the second King of the 4th Dynasty c2589-2566 BC under the architectural direction of his nephew Hemeniu[vi] . It was built using stone and copper tools, by a workforce of several thousand workers who lived and worked on the Giza plateau. Evidence offered for this includes numerous Graffiti in the relieving chambers above the Kings Burial Chamber that name various building gangs of Khufu. One graffiti appears to begin on the block in question below the point at which the block abutting it rests, so logically it could not have been added later when the block was in situ within the pyramid as some have suggested. As this block was found in the highest relieving chamber deep inside the Pyramid, also logically, this must mean it was built by Khufu’s workmen[vii]. Other evidence relates to the workman’s city that has been uncovered on the Giza plateau, that seems to have housed some 2000 workers and includes, in addition to barracks, large bakeries and slaughterhouses that it is proposed were used to feed the workers, this site has been extensively excavated by AERA under the direction of Mark Lehner. All of the dates uncovered in this city however relate to Khafre and Menkaure, so it seems that the location of the housing for Khufu’s workforce has yet to be discovered [viii]. It may well be under Cairo. A final piece of evidence is a papyrus docket that relates to the delivery of stone to the plateau via the Nile, by Captain Merer that dates to the highest known regnal year of Khufu [ix].
The Radio-Carbon Test Results Two studies performed a decade apart (1985 University of Washington and 1995 Supreme Council of Antiquities), both involving Robert Wenke and Mark Lehner, gathered many samples of the mortar from the Pyramids at Giza and ran calibrated radiocarbon tests on the results. Both studies returned results that did not agree with the conventional dating by an average of 374 years. A third study performed by the University of Oxford (Ramsey et al) in 2010 used a different technique using Bayesian algorithms to remove the “old wood” factor from the results. The “old wood factor” was the suggested reason that the results were so wildly “wrong” [x].
Radiocarbon dates taken from wood that is from the centre of trees will return an older date than wood from the outside (or younger portion of the tree). It is suggested that in all these results it must be central wood that is being used in the mortar, or very old wood that had been hanging about for a long time before ending up in the mortar. It should be remembered that wood in Ancient Egypt was scarce and precious. Therefore, it is most likely that the wood used in mortar would be the discarded wood that was removed from the outside of a log as the timber was shaped into planks and blocks for use in furniture and building beams, rather than the other way around, surely? So, while some of the wood used in mortar might be old wood finding its end-of-life use in mortar, it doesn’t seem plausible that all of it falls into this category, does it?
By removing the extreme higher end dates, applying the Bayesian algorithm and averaging the averages, the Ramsey et al study returned results only 76 years older than the conventional dates. These dates being closer to the conventionally accepted dates are gaining acceptance and are now a decade after they were first published) being considered as a possibly authentic and reliable set of dates [xi]
In 2020, a fragment of wood found in the Queens Chamber of the great pyramid in 1872 was rediscovered in the University of Aberdeen’s collection. It was radiocarbon tested by Waymann Dixon and returned a date range of 3341 – 3094 BC [xii].
What does all this mean? The results of the 1985 study were ignored by mainstream Egyptologist’s because they did not agree with the conventionally accepted dates. The 1995 study that was supposed to invalidate the 1985 dates did the opposite and was therefore explained away by the old wood theory. The 2010 study used another technique to disguise the results and return a more acceptable date. The 2020 dating of the Aberdeen wood however confirms the original dating along with many other studies of Old Kingdom, Early Dynastic and Pre Dynastic dates [xiii]. Ian Onvlee has done an extensive study of this and provides a detailed discussion of the suppressed evidence in his series of papers in Egyptian Chronology [xiv] . I will address the wider point of the Egyptian Chronology in another post. Suffice to say that according to the science of radiocarbon dating (in defiance of expert Egyptological opinion) the Pyramids on the Giza plateau appear to be much older than we currently expect them to be: on average 374 years older but with a date range of 3809 BC (+-160 yrs) – 2853 BC (+- 104 yrs).
Making Sense of the Results Most surprisingly the oldest dates were recovered from the highest courses of the Great Pyramid. These would have been covered by the outer layers of Tura Limestone with which the pyramid was dressed. It is counter intuitive to think that the oldest results would be found in the highest layers, we would expect them to be found in the lowest courses if the Pyramid was built over an extended period, surely?
Add to this the puzzle of the Gangs of Khufu graffiti found deep inside the Pyramid and we have a conundrum indeed. The youngest evidence appears inside the Pyramid, up inside the relieving chambers, signed by workers concurrent with Khufu of the 4th Dynasty. Logically it follows that the Pyramid was built by Khufu in the 4th Dynasty. But Khufu is dated by Egyptologists to 2566 BC, whereas our calibrated radiocarbon dates give us a range of 3809 BC – 2853 BC. Even the lowest possible date (2853 – 104 years) puts us at 2749 BC, 183 years too early for Khufu under the currently acceptable dates. What then can we do with this information? Ignore it as mainstream Egyptologists do? Or embrace it as private researchers do?
Theory 1: Khufu built it, but the OK dates are out by 400 years
If we accept that Khufu built the Great Pyramid as the Graffiti strongly suggests he must have, and we accept that the radiocarbon dates are correct, then Khufu built it: 400 years earlier. What does that mean? It would mean pushing back the dates for the Old Kingdom by that many years (allowing for the margin of error associated with radiocarbon dates). That gives us a date for Khufu circa 2996 BC. But, does that explain the wide range of dates produced by the results of the studies? Does it address the other pieces of evidence for which there are no satisfactory explanations (yet)?
Like the fact that we haven’t found evidence of the workforce employed by Khufu; like the fact that the even with an extended reign of say 46 years (many Egyptologists assign him a reign of only 23-27 years, Manetho gave him 66), it would require a rate of deployment of 11 blocks per hour to place 2.3 million blocks in 46 years, assuming working 365 days per year and 12 hours per day. That is ignoring all the other work associated with building the complex such as mining the rock, transporting it, building the valley and mortuary temples, the causeway (which was highly decorated according to the fragments found), digging the boat pits, making the boundary wall, laying the pavement stones… Was it possible, no matter the size of the workforce, to produce this much masonry and lay it in place with such precision in 46 years? Assuming you had a workforce big enough to accomplish it, and they didn’t get in each other’s way moving around the edifice, assuming the administrative capability to efficiently plan and run such an enterprise and the economy to support it in those 46 years. Assuming all that was possible, how do we also explain the following anomalies:
Latest dates obtained by Surface Luminesce Dating (SLD) have revealed that Menkaure’s Pyramid may be older than the Great Pyramid by a further 450 years, with a date of 3450 BC [xv] on the smoothed face of the granite base which would be the youngest part. If dating had been done on the unsmoothed parts presumably even older dates might be obtained.
Boat pits associated with burials first appeared in Dynasty I and the boats themselves have been carbon dated to 3400 BC [xvi] . An inscription from the Eastern boat pit of the Great Pyramid reads 11th (cattle) census [xvii].
The Great Pyramid descending passage is aligned true North with the polestar Thuban (Alpha Draconis) as it was in 2830 BC [xviii].
Why was the Great Pyramid built so close to the escarpment edge? Especially if it was built first? This makes no real sense unless there was a good reason to build it on the exact spot it occupies.
The base was perfectly levelled in the corners and each side is perfectly aligned to the compass directions of North, South, East and West, but in the centre there was a natural mound that was not levelled, instead it was built over.
Tombs were built from year 5 of Khufu on the west side of the Pyramid and from year 12 on the east side, making access to the Pyramid difficult [xix].
Given all of the above, can we comfortably conclude that the whole Great Pyramid complex was built from scratch, by Khufu in 46 years or less?
Theory 2: It was built by another earlier ruler and finished or refurbished by Khufu What evidence is there to support the idea of the Great Pyramid being built by an earlier ruler? Firstly, the radiocarbon dates suggest very strongly that the Giza Pyramids were built at least in part, much earlier than the currently acceptable dates for the 4th Dynasty. And even if we push Khufu’s dates back by a hundred years or so they are still too early for Khufu to have been the sole builder of this magnificent edifice. Secondly the radiocarbon dates for the Great Pyramid, in particular, further suggest that there was a succession of building periods or phases in its development over a period of a millennia or at minimum 450 years.
The evidence strongly supports the idea that the relieving chambers above the Kings Chamber were built or at least repaired by Khufu’s men and the Pyramid’s casing stones were likely put in place by Khufu along with the now lost mortuary temple, causeway and valley temple. The boat pits likely date to the earlier construction but may have been augmented by Khufu’s men as the existence of an inscription attributed to his reign suggests. The purpose of the Gallery as storage for the portcullis blocks to seal the entrance to the Kings Chamber seems likely. Therefore, it is also likely that the Gallery was constructed by Khufu’s men too, the prototype for this is found in the satellite pyramid of the Bent Pyramid at Dashur. However how to explain the early dates in the mortar at the top of the Pyramid? The most likely explanation is that Khufu’s team dismantled part of the pyramid on the Northside to get access to the middle upper part to build the Kings Chamber and gallery leaving the upper courses on the SW side (where the old radiocarbon samples dates were found) intact.
The suggestion that the base of the Great Pyramid, including the subterranean chamber and queens chamber, may pre-date Khufu seems at least plausible, but should be seen in context with other activity on the Plateau. It is also probable, based on the dates, that the upper parts of the pyramid were completed prior to Khufu but were partially dismantled and rebuilt by Khufu when the Kings chamber and gallery were added. This would make the completion of the complex during Khufu’s reign still a remarkable feat, but much more plausible in terms of available time to complete, since the bulk of the core stones would have already been cut and transported to the site.
Conclusion In conclusion it seems at least plausible that the Great Pyramid was built successively over an extended period of time and repaired, rebuilt, repurposed or finished by Khufu. Nothing in the available evidence precludes this interpretation. In fact, the available evidence tends to support it. The evidence also suggests that a serious rethink of the dates for the Old Kingdom is warranted and that it is on balance likely that these dates are out by at least a century and possibly as much as four centuries.
 Wikipedia gives 27 years. https://en.wikipedia.org/wiki/Great_Pyramid_of_Giza
 Shaw’s Chronology has been used here, this is the low chronology and the most widely accepted by Egyptologists today.
 Bauval and Hancock make reference to The Pyramids radiocarbon dating project directed by Mark Lehner conducted in the 1980’s and quote Lehner “The dates run from 3809 BC to 2869 BC…the Giza pyramid is 400 years older than Egyptologists believe.” The reference for this is given as Venture Inward, Virginia Beach, May-June 1986, p 13. Venture Inward is the Journal of the Edgar Cayce Foundation. I was not able to obtain a copy of this volume to check the reference myself. Bonani et al’s publication summarises the results of the 1995 study and references the earlier study briefly. The article How Old are the Pyramids published on AERAWEB 2020 (and I think written by Lehner) summarises both studies. A more recent study by Dee et al 2010 has given less controversial dates. This is discussed further below. The most recent dates (2020) come from the Aberdeen Wood study (BBC).
[i] See the AERAWEB article How old are the pyramids?, for an explanation of the Old Wood problem which is used to discount the results. See also Ramsey et al 2009
[ii] Aberdeen wood dates, see BBC News 16 September 2020
[iii] See Wikipedia entry for the Great Pyramid link above.
[iv] Verner 2001 p373
[vii] See my comments footnote iii
[viii] Ramsey et al A Radiocarbon based chronology for Ancient Egypt.
[ix] BBC News 16 September 2020
[x] Onvlee 2016
[xi] You can find these on Research Gate https://www.researchgate.net/search/publication?q=Ian%20Onvlee
[xii] Li Liritzis, Ioannis & Vafiaou, Asimina 2014
[xiii] Onvlee, Ian The great Dating Problem Part 2 (Researchgate) pg 34 Note Onvlee states this: “The 3400 BC date also corresponds with the Pole Star Alignment Theory for the construction date of the Great Pyramid which holds that the descending passage was aligned with the polestar Thuban (Alpha Draconis) in 3434 BC, now more precisely calculated to be 3410 BC.” However I have not been able to find an independent reference to back this up and he doesn’t cite his source. I have found an article in the NY times that gives the date 2627 BC for the alignment of Thuban with the North Pole (correcting Kate Spences calculation of 2467 BC) and Wikipedia gives 2830 BC as the date for the closest alignment with the Pole (to withing 0.02 of a degree) which is the closest alignment of a pole star with the North Pole recorded.
[xiv] Verner 2001
[xvi] Hawass 1988
Altenmuller, Hartwig Funerary boats and boat pits in the Old Kingdom Archiv Orientalni Vo 70 Number 3 August 2002 p269-290 (Digital Giza)
Ancient Architects https://www.youtube.com/channel/UCscI4NOggNSN-Si5QgErNCw
AERA How Old are the Pyramids? 2020 http://www.aeraweb.org/projects/how-old-are-the-pyramids/
Arnold, Dieter Building in Egypt: pharaonic stone masonry OUP 1991Bauval, Robert and Hancock, Graham Keeper of Genesis 1996
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Ramsey, Christopher Bronk et al “Reanalysis of the Chronological Discrepancies Obtained by the Old and Middle Kingdom Monuments Project”. Radiocarbon. 51. 2009
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