The Forced Entry of the Caliph into the Great Pyramid of Giza

Tunnel Vision – The Mysterious Forced Entry of the Caliph into the Great Pyramid of Giza

The classical account of the discovery of the upper chambers inside the Great Pyramid at Giza is well known. In the ninth century an Arab governor of Cairo, known as the Caliph al Ma’mun, decided to see for himself what lay inside the Great Pyramid. Because the entrance to the pyramid was concealed and its location unknown, his workers began to excavate a tunnel boldly through the casing and core blocks, with hammers and chisels. Fortuitously for the Caliph, their busy tunnelling shook the structure so much that the capstone fell off the end of the ascending passage. The resonating crash was heard by the workers, who dug in that direction and found not only the descending passage, but also the ascending passage and all the upper chambers in the pyramid. After thousands of years lying undisturbed deep inside the Great pyramid, the King’s and Queen’s chambers were finally open, and their treasure would soon belong to the Caliph.

But, as the story goes, there was no treasure. Apparently, this most ancient and precious of cupboards was completely bare. There were not only no burial artifacts, but no burial and no inscriptions either! The first thought to cross the mind of the Caliph must have been that the ‘tomb’ had been robbed. But how? Even if the secret ‘Well Shaft’ deep inside the pyramid had been found at this stage, it is hardly a suitable tunnel through which to strip a wealthy burial chamber totally bare. So where was all the loot? The Caliph and his excavators must have not only been very exasperated, after all their work, but mystified too.

A cross section through the Great pyramid of Giza
Fig 1 - A cross section through the Great pyramid, looking west and showing the internal chambers.

Mamun's tunnel

Are we so sure that this is what really happened, just over a millennia ago? Are we simply complacent because this is what has been taught to us by respected authorities for centuries? After all, it is much easier to simply agree with the established consensus of opinion, rather than thinking positively and laterally about the problem. Fortunately there are a few individuals out there who are more than happy to challenge a whole raft of classical myths; and so it was one day that a short e-mail arrived in Ralph Ellis’ in-box from a like-minded colleague, Mark Foster. Mark had an idea that had been bothering him for some time and he wanted to throw it around a bit. A quick read convinced Ralph that it was a highly original idea and definitely worth some further thought. After a few debates here and there, the following alternative scenario to the classical story developed, which is quite attractive in many respects. Yet this new explanation not only answers some irritating puzzles, it also poses some interesting and fundamental questions in return.

Caliph al-Ma'mun's forced entrance into the Great Pyramid

Fig 2. Caliph al-Ma'mun's forced entrance into the Great Pyramid, which tracks directly towards the join between the ascending and descending passages.

As Mark explained, the basic problem with the classical explanation was that Ma'mun’s tunnel is rather too accurate for comfort: it tracks into the pyramid in a direct line for the all-important junction between the descending and ascending passageways. It is often cited that Ma'mun had to turn the tunnel sharp left to discover the original passageways, a fact that Ralph and Mark had in the back of their minds when they first visited the Great pyramid. But as Ralph and Mark ambled down the forced tunnel, they were both rather mystified, because the ‘left turn’ cited in the literature could not be found! Having backtracked the tunnel and tried again, that ‘left turn’ seemed to be no more than a slight widening of the tunnel at this point. In actual fact, the diggings were almost right on their target. So how did this happen, was Ma'mun just lucky and happened to pick the right spot? Or did he have an idea of where to go to?

The entrance to the Third Pyramid of Giza

Fig 3. The entrance to the Third Pyramid. Note how the granite blocks have been smoothed down around the entrance, which clearly marks its location.

There is also the problem of why Ma'mun was  tunnelling inside the pyramid in the first place. Not only was the presence of the true entrance to the pyramid well known in classical times but people were also aware of the descending passage and the subterranean cavern at the very bottom of the pyramid. Strabo says of the original entrance to the Great pyramid:

The Great Pyramid, a little way up on one side, has a stone that may be taken out, which being raised up there is a sloping passage to the foundations. 1

Strabo seems to be describing a door made of stone that is movable in some way, it can be moved upwards and outwards at the same time. This sounds like a hinged flap arrangement, with the hinge at the top of the stone. So was this description mere fantasy, or historical fact? We do not exactly know, but Strabo was obviously very familiar with the internal layout of the lower portions of the pyramid as he calls the lower cavern 'the foundations’, rather than using the more obvious term ‘chamber’. And Strabo is right, because the void below the pyramid is much more of a rough-hewn cavern than a smooth rectangular chamber.

And we know that the entrances to the Giza pyramids were known about in ancient times, because some of them are quite obvious. Take a look at the entrance to the Third Pyramid, where only the stones around the entrance have been smoothed down. Nobody could mistake the position of the entrance to this pyramid, and it is likely that the position of the entrance to the Great Pyramid was equally obvious. But it is important to note that the ascending passage in the Great Pyramid had been carefully concealed by the builders, so nobody in this early era knew about the Queen's and King's chambers high up inside this pyramid. The only chamber in the Great Pyramid that was open and known about in this era was the rough cavern at the very bottom of the pyramid, which Strabo accurately terms as 'the foundations'.

The second entrance to the Vega (Bent) Pyramid

Fig 4. The second entrance to the Vega (Bent) Pyramid, which is located high up on the western face of this pyramid.

Sir Flinders Petrie backed this quotation up with a detailed study of the entrances to the Vega (Bent) pyramid, the only pyramid that still has the doorways around the entrance intact. He found that on either side of the entrance, there were holes cut opposite each other, about 9cm in diameter by 14cm deep. These holes were just inside the entrance and only 15cm from the top of the passage. Petrie, not unreasonably, interpreted these as being the hinge sockets to swing the stone door from.

Behind these sockets, the passageway contained more door sockets. These were smaller vertical sockets, for a very lightweight door, perhaps made of wood and presumably to keep out the wind-blown sand. The diagrams below were developed by Petrie, based on his analysis of the Vega (Bent) pyramid entrance. The hinged stone door is clearly marked as the large shaded stone. It needs to be this shape, with a long top extending backwards, in order to counterbalance the weight of the stone. The amount of counterbalance at the top would have been judiciously arranged by the architect, so that the force required to open the stone was within normal human limitations, say about 25kg of force.

Entrance door

Great pyramid’s entrance closed and opened

         Fig  5. Great pyramid’s entrance closed and opened

Here then, we have clear evidence that a movable entrance stone was fitted to the Great pyramid, and that the descending passage had been visited, perhaps many times, throughout recorded history. To gain entry to the pyramid, however, was still not easy. Unless there was a flight of steps cut into the now-missing casing blocks, a series of ladders would have to be erected against the side of the pyramid to reach the door. Presumably the entry stone must have had a handle of some sort on which to pull, and it would then need a prop of some nature to keep it open, while the new initiate scrambled into the thin hole and down the descending passage. A knotted rope would also have to be fed slowly down the length of the passage, to allow for an easy exit from the dark and foreboding depths of the sacred pyramid.

Undoubtedly, all of this frenetic activity would have scratched and pitted the entrance to the pyramid over the millennia in a very obvious fashion. Yet, it is generally accepted that the casing blocks must have been intact during the rule of Ma'mun, as the casing blocks appear to have been used by Sultan Hasan for the construction of his mosque in 1356.

The layout of the chambers inside the Great Pyramid

Fig 6. The layout of the chambers inside the Great Pyramid. Note the rough cavern right at the very base - the 'foundations', as Strabo described it.

The question is, therefore, why could Ma'mun not see these tell-tale marks and the original entrance to the pyramid that lay only a few meters above him? Why could he not see the handle on the door, or the scuff-marks on the smooth exterior? And knowledge of the location of the true entrance must still have been known in this era, so why could none of the locals be ‘persuaded’ to point it out? And this apparent invisibility of the original entrance could not have been because it was covered by sand, for instance, because Ma'mun’s tunnel lies below the level of the real entrance. So what was the problem? Why so was much effort expended in digging a new tunnel, when the original entrance lay just above it?

Some very important questions have been posed here – why could Ma'mun not see the real entrance to the Great Pyramid, when it was so well known and so close to his own entrance? And if Ma'mun did not know where the real entrance was, then why was his alternative tunnel so accurate? But if the original entrance was known about, then how did Ma'mun discover the ascending passage, which had been carefully concealed when the pyramid was first built? This is a bit of a catch-22.

Part 2 – why did Ma’mun really create a forced entry tunnel?


1.  Strabo. Quoted from Pyramids and Temples of Gizeh, Flinders Petrie.

The article ‘Tunnel Vision’ has been extracted with permission from ‘Thoth, Architect of the Universe’ by Ralph Ellis and ‘K2, Quest of the Gods’ by Ralph Ellis, available from

Featured image: The tunnel of Ma’mun. Source: Wikipedia

By Ralph Ellis and Mark Foster


rbflooringinstall's picture

History is always getting twisted up.

Peace and Love,


angieblackmon's picture

so many questions....and ideas and half answers that only lead to more questions....

love, light and blessings


nisa burkay's picture

Perhaps Ma'mun was afraid there were traps in the "original" entrance? Superstition? Especially if they still believed it was a tomb. in those days.

Nisa Carroll Burkay

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