From Djoser to Khufu: The Rise of the Pyramid I SLICE HISTORY | FULL DOCUMENTARY

Two hours from Cairo, we come to the immense Fayyam Oasis. This is where King Amenemhat III chose to build his pyramid. Zahi Hawass is one of the most famous Egyptologists in the world. For him, this pyramid is one of the most fascinating. It is an abundant pyramid, but it's an amazing one. Because if you look at the construction of this pyramid, it's a miracle of how the Egyptians constructed this pyramid. It's something amazing. At its completion, Amenemhat III's pyramid cut an impressive figure. It stood on a large base more than 105 meters wide and was 58 meters in height, the equivalent of the first floor of the Eiffel Tower. But how did it come to be in its present state? What happened to compromise the pharaoh's plans to this extent? Amenemhat III was the most important pharaoh of the 12th dynasty. He reigned at the time of the Middle Kingdom, 800 years after the construction of the famous Pyramids of Giza. Times had changed since the construction of the giant pyramids of the Old Kingdom. The means and the architectural techniques were no longer the same. They switched from building pyramids of stone to building them of mud brick. Construction was far simpler. Wherever you were in the territory, transportation was easier. This clever construction method was a time and energy saver, added to which it had no impact on the final appearance of the pyramid. And ultimately, those mud brick cores are faced with limestone, so they look exactly like an Old Kingdom pyramid. Once finished, the Hawara pyramid shone out brightly. It was in fact covered by a facade of slabs of stone with remarkable qualities. It was a particular limestone, known as Tura limestone, which is extremely white and very pure. To draw a somewhat anachronistic comparison, it's almost the marble of Egypt. The Tura limestone covering, with its crystalline nature, reflected the rays of the sun. This represented the solar nature of these constructions and meant that they were visible from a great distance. Further north, on the other side of the Nile Valley, the Tura quarries are totally unique in Egypt. They supplied limestone of extremely high quality and sparkling whiteness, with which all the country's pyramids were covered. You have huge teams of people who would be chiseling it down and cutting it into blocks. There it would be taken slipways and brought to the Nile. Once the blocks had been cut, they were transported to the construction site by boat. Each pyramid area would have a canal, so that boats could bring these large blocks there. Then they were taken on causeways, on big sleds, and they would be dragged by teams of workmen up to the pyramid. However, there was one element which the pharaoh did not anticipate. The devastating activities of stone thieves. From antiquity, these robbers simply helped themselves from the pyramid and reused the blocks for other constructions. Over the centuries, they totally stripped it of its covering, leaving it completely naked. The effects of time did the rest. The resemblance to a crumbled sandcastle which it has today was brought about by rain, time and wind erosion. Everything caused it to sag, it was destroyed. The edifice now only stands 20 or so meters high, less than half of its original size. But, beneath this pile of bricks, it is in the very entrails of the monument that the true genius of its construction can be found. The problem is, no one can go inside to study it. The pyramid has been inaccessible for more than a century, because it is totally flooded. This was caused by groundwater seeping up from the phreatic zone. Look, beside the pyramid, you have agricultural land and you have canals. All the water comes here and they began to be stuffed completely in the burial chamber. These images are absolutely exceptional. They are the only ones taken inside the pyramid during the dive of an underwater robot in December 2019. It managed to film the beginning of the corridors. But the vast quantities of sediment which had accumulated were churned up by the water, making exploration very difficult. Nonetheless, one thing is clear from these images. Despite the thousands of cubic meters of water attacking the interior, the internal structure of the pyramid is incredibly well preserved, proof of the quality of conception. I don't understand how the burial chamber and the pyramid still exist of this water. When I came here like 12 years ago, I could not believe that this pyramid would stay until today. It's been flooded for a very long time, even in the 19th century. But despite that, the stone has managed to withstand the vicissitudes of nature and time very well. And it is extraordinarily surprising that it has done so. Thanks to the determination of 19th century explorers, the last to have entered the pyramid, we have a good description of the interior. They noted that Amenemhat III's architects had invented the first high-security pyramid. We have some really sophisticated approaches taken to security. This wasn't the first time that closing systems had been used to prevent thieves and pillagers from entering a funeral chamber. However, the complexity of this system was a first. The treasure which accompanied pharaohs in their tombs attracted pillagers. The constructors were well aware of this, and to outwit them, they built a new style funeral chamber. You could say that Amenemhat III has a sort of a strong box, or a vault for a burial chamber. The casket was inserted directly into a block of massive stone, intended to make the pharaoh's resting place impenetrable. What the Egyptians did, I think, before they built the pyramid, they cut in the level on the ground a big, large square. Then they had one big block, 100 tons weight, and they put it in that square. Then in the middle, they cut a space, and they put the sarcophagus inside that space. But how could such a heavy block of stone be manipulated? The builders came up with a particularly ingenious system. Two narrow shafts, filled with sand, were dug at the sides of the chamber. The last of those blocks, which was held in place, open before the king's interment, is held up by two struts made of stone, which are slowly lowered into the chamber by means of sand. All that remained was to remove the sand from the side cavities, so that the block would descend to its final position under the effect of gravity. A true technical exploit. Just using the displacement of sand, the Hawara pyramid builders managed to close a stone slab weighing several tons over the remains of the pharaoh. With such meticulous means of protection, this tomb was intended to ensure the eternal tranquility of Amenemhat III. Yet the plans failed. When 19th century Egyptologists entered the pyramid, they found it completely emptied and ransacked. Here, as elsewhere, the defenses had been totally ineffective. The pyramids were all broken into very early on. None of the protection systems outsmarted the pillagers. Thieves managed to get around all the protection systems, almost certainly because they were informed about precisely how the pyramids were constructed. Despite the damage done by looters, the interior of the building undoubtedly still retains numerous secrets. But as long as it remains inaccessible, any wide-range study of these apartments is impossible. In sixth position, here is a pyramid which doesn't even appear to be one. And yet this mound, standing barely 10 meters high, conceals one of the most incredible secrets of the pharaohs. Some 15 kilometers from Cairo stands Saqqara, the biggest necropolis in Egypt. In its southernmost part can be found a fantastic funerary complex around the pyramid of Pepi I. Pepi I pyramid complex could be regarded as being the most elaborate of its time because it incorporates a huge number of subsidiary pyramids belonging to members of the royal family. It was pharaoh Pepi I who had this surprising pyramid built around 2300 BCE. He was the third king of the sixth dynasty, the last phase of the old kingdom. The golden age of pyramid builders was coming to an end. From above, the vast expanse of this complex, today largely in ruins, becomes apparent. It covers a total of 4.7 hectares, the equivalent of more than six football pitches. Upon its completion, it was one of the most beautiful funerary complexes ever built in Egypt. A superb pyramid surrounded by magnificent, finely decorated temples and satellite pyramids. In the center is the pyramid of the king, around which you have the necropolis of spouses and royal children, essentially in the form of pyramids. And in a third circle, you have the necropolis of nobles. It had a great temple with beautiful stonework, paintings and so on. 4,300 years later, hardly anything remains. Stone thieves carried off virtually everything. Today, it's a hillock, totally shapeless rubble, which looks more like a dome or a pile of stones than a pyramid. In the 19th century, a group of French archaeologists were determined to find out what was hidden under this pile of sand. With great effort, they reached the interior. What they found there left them speechless. The walls were covered in hieroglyphics. When archaeologists entered the pyramid of Pepi I, it was the first time funerary texts had been found in a pyramid. It was extraordinarily beautiful. It's really stunning to go in there and to feel oneself surrounded by the magic of these spells. The discovery of the pyramid texts is extremely important because it brings to life previously silent monuments. No hieroglyphics had ever been found in any of the previously explored pyramids. Now, here were walls totally covered in them. But Egyptologists were perplexed. What could these mysterious hieroglyphics possibly recount? Why had the pharaohs had them engraved here? In deciphering them, they came to understand the fabulous nature of these texts. The texts in the pyramids were magic formulae permitting the sovereign to escape from his enemies and demons in order to finally reach the kingdom of the gods. The study of these texts, the totality of these writings, these incantations, these magic formulae, clearly shows that they were designed to accompany the regeneration of the king in his tomb and his journey to the exterior. Once engraved, the formulae were painted green, a color not chosen at random. It symbolized Osiris, the god of resurrection, and had a very particular function. The very logic of these texts leads from the interior to the exterior. In a certain way, they accompanied the king's exit from his tomb. You have a series of lists of offerings, a little bit like a shopping list, which were the indispensable survival elements for the deceased. All across the ceiling, hundreds of stars were drawn. They represented the celestial dome. While exploring the other pyramids of the 5th and 6th dynasties, archaeologists discovered that these texts were actually engraved in all the pyramids of this period, 11 in total. Collectively known as the Text Pyramids, they are all to be found at Saqqara. South of the Saqqara necropolis, Dahshur stands on a desert plateau, 30 kilometers from Cairo. Marc Lanier has been studying the Egyptian pyramids for more than 40 years. Ever since he started out as an Egyptologist, the Bent Pyramid has fascinated him. The most prominent thing about this pyramid, it's bent. And this is the result of Sneferu's experiments. So what you're looking at, really, is the research and development, the R&D that led to the Great Pyramid of Khufu. Sneferu was the founder of the 4th dynasty, the most well-known in Egypt, and the father of the famous Khufu. He reigned around 2600 BCE. This was at the time of the Old Kingdom, the thriving period during which the giant pyramids were built. Egypt was at its height. I would say that it is during this reign that the Egyptian state attained adulthood, with the valorization of its agricultural territory never before seen. Sneferu is able to use resources from all around Egypt, including people, towards a national project, in this case, the building of pyramids. Before Sneferu, all Egypt's pyramids had been built in the step pyramid form, resembling staircases. But this pharaoh wanted to revolutionize everything. He demanded from his architects a technical prowess hitherto unheard of, the construction of a smooth-faced pyramid. The initial project was monstrously ambitious. This first project for a pyramid with faces sloped at about 60 degrees was intended to reach a height of 130 meters. With a base width of 157 meters, it was the largest ever built in Egypt. The very steep 60-degree faces should have resulted in a pyramid with a phenomenal height of 136 meters, something never before seen. Nobody knew what a pyramid should look like, a true pyramid. The evidence is that the 60-degree pyramid was too steep. With the burial chambers already completed, this overly audacious project was suddenly modified. The first pyramid project was curtailed at a certain height. They perhaps realized that it was extremely difficult to reach such heights with such steeply sloping sides. So the idea is that his workers said, oops, and they put a girdle, a brace around this steep 60-degree pyramid at the lower slope of about 54 to 55 degrees. And then they started to build up, now with a fatter pyramid. A thick envelope of masonry was therefore added to all four sides of the building to consolidate it. This greatly reduced the angle of the slope. This enlargement brought consequences which were totally unexpected and disastrous. Egyptians had not envisaged differential settlement. That is to say, the outer layer became lower, it sank slightly. The foreman and the architect realized that there were technical problems, cracking, subsidence. They began to fear the worst. The pyramid could have collapsed. It should be noted that Seneferu had committed a major error in the choice of site for building his edifice. The fundamental problem with the Bent Pyramid was the bedrock on which it was built. It clearly wasn't up to supporting the sheer weight being piled above that. He was building on the natural desert surface, the clay and the gravel. And this is not substantial enough to support such a large pyramid. As the pyramid grew, its weight increased, pressing down ever more heavily on the unstable foundations. To avoid a catastrophe, the pharaoh's architects needed a hasty change of strategy. So it was decided to create a second slope in an attempt to reduce the weight of the finished structure. So they had to change the incline of the slope to reduce the weight on the top of it. And this stopped it collapsing completely. The top of the pyramid was finished at the shallower angle of about 43 degrees. The work was completed hastily. On the upper part, the blocks of the facade were placed quite haphazardly. It's very clear that the Egyptians wanted to finish the monument quickly. Thanks to the adaptative skills of its creators, the pyramid nonetheless reached the incredible height of nearly 105 meters, equal to that of a 42-story building. It was the first pyramid in history to exceed the height of 100 meters. Despite the relative architectural disappointment which it represents, the Bent Pyramid is paradoxically the one which has best weathered the centuries. It was, in fact, the way in which the blocks were positioned which protected it from stone thieves. The Bent Pyramid, in fact, presented them with an obstacle. The blocks were much more difficult to detach and drop to the ground. Sneferu's builders are setting blocks at an incline. You see, they're tilting them a little bit in towards the core of the pyramid. Actually, it's the incline of the casing blocks that made them difficult to rob. And that's why you have more casing on the Bent Pyramid than any other pyramid. Over the centuries, this Tura limestone covering has lost its sparkling whiteness. Through contact with the air and the rain, it formed a protective coating, and this is what has given the stone this beige tint. But with more than 70% of the façade preserved, the Bent Pyramid is today the best conserved in Egypt — a satisfying sign of defiance. Nonetheless, for Sneferu at the time, the project was a failure. He didn't achieve the perfect pyramid. But the pharaoh wasn't somebody who gave up easily. He simply decided to have a third pyramid built — larger, more stable, more perfect — the Red Pyramid. In fourth place, the very first successful smooth-faced pyramid — the Red Pyramid. Its construction was a true architectural revolution and the triumph of Sneferu. At 108 meters in height, it established a new record. This less famous pyramid is nonetheless the third greatest in Egypt in terms of size and impressive volume. To have this new pyramid built, Sneferu didn't search very far. He chose to stay in Dahshur and build the monument at less than two kilometers from the Bent Pyramid. But the Egyptians had learned from the errors committed with the Bent Pyramid. To start with, the choice of site was far better thought out. The Egyptians positioned the Red Pyramid on much more stable ground in that it is rock as opposed to sand or gravel. To satisfy their king, Sneferu's architects took no risks. Their first objective was to ensure the stability of the edifice. For this, the builders had understood that the base needed to be widened to reduce the angle of the slope and avoid the danger of collapse. Nearly 40 meters were added to the width compared to the previous project. The angle of slope thus obtained was identical to that used for the top of the Bent Pyramid. So from the preceding project, Sneferu had drawn a conclusion. He believed he had found the ideal slope for safely building a pyramid. Here they achieved a perfect pyramid with the rather low slope that we see at the top of the Bent Pyramid of 43 to 44 degrees. This is what gives the slightly squat look which is rather surprising but made it the most stable of the three pyramids. With this much shallower slope, the Red Pyramid effectively appeared more stocky, not as slender as the others, but its stability was thereby guaranteed. Another technical improvement. While the previous pyramids had been built with their stone slightly inclined towards the inside of the building, this time a different choice was made. With the Red Pyramid, for the first time, horizontal coursing was used which was definitely more stable. The blocks for each level were all positioned on the same plane and these were placed one above the other until they reached the summit. This was the norm in Egypt for all future pyramids. Somehow in their learning curve, they came to the conclusion that horizontal coursing is the best. After probably more than 15 years of work, the Red Pyramid was finally completed. Although the envelope of the edifice has now totally disappeared, the interior has remained virtually intact. The external perfection of the pyramid is reflected in the interior apartments. For many Egyptologists, I think, the inner chambers of the Red Pyramid are the greatest interiors of any pyramid. Zahi Hawass leads us into the depths of the building. To arrive there, you have to take a particularly steep corridor, the entry of which is higher placed than in any of the other pyramids. And the reason for making the entrance of the pyramid and this corridor to be in a height of 28 meters is to hide it from the thieves. This is why they made the entrance to be that high, different from any pyramid in Egypt. This steep passageway was never intended for visitors. The pharaoh alone was intended to take it, and only once, at the moment of his resurrection. The journey of the pharaoh was to leave the sarcophagus and then to join the stars. So he took the opposite path to visitors, following the tunnel upwards to the north. At the end of the corridor, three magnificent chambers are laid out. Each is covered by corbel arches, intended to consolidate these empty spaces beneath the monument. It's an impressive spectacle. A corbel arch, like with other types of vault, makes it possible to redistribute the load above the chamber towards the sides. This stops the burial chamber from caving in. You have a system of stone beams placed longitudinally along the hall, with the space between the lines being gradually reduced. So you have something like a staircase to the summit. This was something totally new, an innovation of the architect, which was absolutely extraordinary, and made it possible to achieve larger empty spaces. The limestone walls of the chambers were built with astonishing precision. The blocks are perfectly smooth, with extremely fine joints. You cannot even make one needle between them. They never used any mortar. And this type of blocks, they put it between each other in a way, can be like this. The work was so meticulously carried out by the pharaoh's laborers, that when you look at the perfect state of conservation, it's hard to believe that these rooms are around 4,600 years old. The pyramid was not only a tomb. The pyramid was representing the power and the dignity of the king. And therefore, he should show perfections in the construction. The Red Pyramid, or the North Pyramid at Dahshur, built by Sneferu, really represents a kind of pyramid perfection. And it's that model which Sneferu's son, King Khufu, will follow. And basically that becomes the classic pyramid in ancient Egypt. In third place of our top seven stands a pyramid which is too often eclipsed by its neighbor. And yet today, it is the tallest in the world, the only one higher than 140 meters. It is the majestic Pyramid of Khafre, a true architectural masterpiece. We are on the Giza Plateau, the most famous site in Egypt, and one of the world's best known. It is at the western extremity of the Cairo Megalopolis, the center of which is less than 10 kilometers away. Khafre was the first pharaoh of the fourth dynasty to construct a pyramid right next to that of his father, the illustrious Khufu. So why did he make this choice? In order to understand, we need to look into the king's mysterious history. Khafre mounted the throne around 2560 BCE in somewhat troubled circumstances. Khafre is a son of the previous king, King Khufu, but he's not the immediate successor of Khufu. There's another king, a guy called Djedefre. There may be some dynastic struggle there we're not quite sure of. The royal legitimacy of this character at the moment when he arrived in power is unclear. To establish his legitimacy, Khafre made a particularly clever choice, placing his pyramid in direct alignment with that of his father, Khufu, in order to affirm himself as rightful successor. Any question about his lineage would have required an immediate statement to say, I am on the throne, I am legitimate. But Khafre didn't stop there. To present himself as the greatest of pharaohs, he had one single obsession, outrank the pyramid of Khufu, the largest in Egypt. Upon completion, the pyramid of Khafre was over 143 meters in height. It is the second highest pyramid ever built. However, it remains smaller than that of Khufu, the total volume of which was 15% greater. Nonetheless, it is the pyramid of Khafre which appears to be slightly larger than its neighbor. When people visit the Giza Plateau, they're immediately struck by the size of the Khafre pyramid. So the uninitiated, it is actually the most impressive of them. How is this possible? In fact, to satisfy the demands of their master, Khafre's architects proved themselves particularly skillful. Using a 53 degree slope, steeper than that of Khufu, was a first strategy which gave the impression of stretching the edifice upwards. That's what gives it its slender look, much more gracious than the other pyramids. It shows a good knowledge of how things look. And so it just makes it that bit look taller and slightly more impressive than the actually bigger pyramid of Khufu next door. But above all, the builders took great care in deciding upon the site for the monument. Their choice was as simple as it was effective. They placed the pyramid on a rocky promontory. They used a plateau which was 10 meters higher than that used for the pyramid of Khufu. Thanks to this ruse, when finished, the pyramid of Khafre was higher than the pyramid of Khufu. Khafre clearly had picked up the idea of higher ground, higher top. Thanks to the ingenuity of his workers, Khafre's demands were fulfilled. It is indeed his pyramid which dominates the Giza plateau. Even today, specialists are astounded by the level of perfection which was achieved. The precision of the measurements for the pyramid of Khafre is nothing short of prodigious. The faces only differ by a matter of centimeters. The base is almost a perfect square with 215-meter sides, with an average margin of error not exceeding 8 centimeters from one face to another. The right-angled corners are not more than one degree out. But how did the Egyptians attain such precision with the means of the time? The mapping out of pyramids was extremely precise. However, the means were quite rudimentary. We can assume they used ropes and sticks. They also could have used targeting, aiming at target points on the horizon. On closer inspection, it is still possible to observe strange holes in the ground all around the pyramid. They probably hold the answer to the mystery of this extraordinary regularity. The reason for the construction of these holes is to make an accurate square base for the pyramid. All these types of holes were connected with ropes by each other. Workers must have planted wooden posts in these holes, which they linked together with rope to achieve a straight line. Next, they would have used simple tools to obtain a 90-degree angle and sketch out a square. Once the base was drawn, the Egyptians could begin building the structure. Thanks to the excellent limestone of Giza, they could use megalithic blocks larger than those employed earlier. Walking around the pyramid, it is not uncommon to come across blocks of more than 50 tons. The use of blocks with such exceptional dimensions has no equivalent in Egyptian funerary architecture. Everything was thought out to guarantee the perfect stability of the pyramid. The considerable mass of these gigantic stones, which can be more than five meters in length, meant the lower layers were solidly placed on the foundations. Afterwards, as the building grew higher, the volume of the blocks was progressively diminished. They put above the pyramid horizontal blocks, each one in every side, until they go smoothly up to the pyramid. If you see the stones, when you go to the top, it became smaller. Towards the top of the construction, rarely are the blocks of more than a few cubic meters in volume. The idea was to lighten the upper part of the monument so as to better spread the weight over the lower layers. But how did the Egyptians manage to raise stones weighing several tons to such a height? For specialists, ramps are a likely solution. Two main ramp theories exist. The theory of a straight ramp heading straight towards the pyramid and that of a spiral ramp encircling the structure. Frontal ramps have the obvious advantage of being straight, making transporting the blocks easier. On the other hand, they have the inconvenience of having to start a very, very long way back. Whereas if you have more of a spiral ramp, you can do a lot more building from all the different sides. You're not as restricted in traffic and so you can build a pyramid much faster with a, in fact, smaller workforce. The Pyramid of Khafre was to be the last giant pyramid built in Egypt. No future pharaoh managed to attain such colossal dimensions. No future pyramid was to reach half of its maximum height. On the second step of the podium stands the Pyramid of Djoser, the very first pyramid in history of humanity. The unusual staircase shape of this edifice is immediately disconcerting for any observer who likes to think of pyramids as triangles. It is what is called a step pyramid. The Pyramid of Djoser was the very first of its kind. We return to Saqqara and the most expensive necropolis in Egypt. This is where, close to the capital of Memphis, Djoser chose to erect his tomb. The reign of this pharaoh began at around 2700 BCE. He was the founder of the Third Dynasty. Djoser succeeded in unifying the country as no one had before him, thereby sparking an age of prosperity hitherto unknown. The Old Kingdom. With the rediscovered territorial unity and the unified state, King Djoser had the means to undertake a monumental construction at a level unlike that of any of his immediate predecessors. Reunifying the whole of Egypt meant a vast labor force was available for constructing his monumental funerary complex. It is estimated that the colossal works lasted 20 years and above all, such an exploit was rendered possible by the skill of one man, Imhotep. Imhotep, the great royal architect, was chosen by Djoser to build his funerary complex. He was brilliant, something of the da Vinci of ancient Egypt. Egyptian tradition regards him as an extremely important character, so important in fact that at the end of Egyptian history, he was even deified by the Egyptians. So how did Imhotep go about building such an edifice? How did the idea of creating a pyramid even come about? To try to shed light on this mystery, archaeologists concentrated on the monument structure. To their immense surprise, they discovered that at the outset, it wasn't even a pyramid at all. Originally, it was just a simple mastaba. The word mastaba comes from an Arabic word for bench. So these are relatively low, flat structures. Mastabas were rectangular clay brick constructions, which were the earliest examples of royal tombs. Up until then, all Egyptian buildings had been made from mud bricks, which were easy to produce and transport. But the major inconvenience was that these bricks disintegrated with time. So in order for this tomb to weather the centuries, Imhotep came up with a fabulous idea. For the first time, he replaced bricks with stones. The idea behind stone construction was to create sustainability. And last for eternity, which is the very point of a tomb. Despite this innovation, Djoser was apparently dissatisfied. The pharaoh ordered his architect to produce a still more spectacular tomb. Imhotep began by enlarging the original mastaba. So they added another layer over the top, and then a second one. When they saw that this held firm, they decided to enlarge it. But Djoser still demanded more. And that's when Imhotep suddenly had a flash of inspiration. A simply brilliant idea. Making a stack of mastabas. If you want to really impress someone, you pile them one on top of the other. And that's what the step pyramid is. It is a series of mastaba tombs, one on top of the other, like a wedding cake. The engineers were getting more confident, and then put three more rectangular things on top of it to make it a four-stepped pyramid. And presumably, having discovered it hadn't fallen down, they then enlarged it further to a six-stepped pyramid. That was how, by easy steps, Egyptians invented the pyramid. It was an architectural revolution which would render the pharaohs famous for eternity. Never had man succeeded in building an edifice of such dimensions. With a base of 109 by 121 meters, and a height of over 60 meters, the Pyramid of Djoser became the highest building in the world. This layering created a sort of staircase, a ladder, if you like, to reach the sky so that the soul of the deceased king could attain the gods. It allowed the pharaoh to reach the hereafter, the firmament, and to reign alongside Ra in his perpetual and daily journey. But the pharaoh's project didn't end there. To preserve his grave, Djoser had a spectacular structure built beneath the pyramid, which was undetectable from the exterior. A vast network of galleries of a total length of nearly six kilometers. The interior corridors are probably the most elaborate of any Egyptian pyramid. They are vast. This sort of thing doesn't exist in other funerary complexes. Marc Lanier takes us to the heart of this incredible subterranean palace. Beneath the center of the pyramid, nearly 25 meters underground, the burial chamber of the pharaoh was to hold his remains in an enormous granite cavern, four meters high. Right next to his tomb were the king's sumptuous apartments for his life after death, the blue chambers. You have the so-called blue chambers, which refers to corridors completely covered in multiple pieces of blue earthenware. This is not only a tomb, it is also the representation of a palace of the hereafter, decorated with absolutely magnificent reliefs, which by the way are a first in the history of Egyptian art. Marc Lanier is determined to show us these rooms, which are the most beautiful in the monument. But it's difficult to find your way through such a labyrinth. Coming in here, I'm kind of playing it by ear as we say in English, because I don't know it by heart. But we're trying to find our way to the subterranean symbolic private apartments of the king. Once resuscitated, the soul of the pharaoh was to leave the tomb and be able to wander the apartments. He comes from here, where he's put to rest, and he resurrects, and he goes around the corner into his private apartment. We finally come to this privileged space. All this exquisite work was never meant to be seen. It was 25 meters below the plateau. You know, these chambers, rendered in blue faience, they are really the spiritual heart of the pyramid. This is where the king lived on. This is where his spirit left the mummy in the granite vault and came to live on in the afterlife. In a sense, this is the spiritual heart of the step pyramid complex. Due to pillaging and the ravages of time, much of this superb earthenware has disappeared. But nearly 4,700 years after they were put in place, the finesse and the state of conservation of the remaining pieces is astonishing. This is the pyramid of all the superlatives. It has to be at the summit of our top seven. Khufu, the so-called Great Pyramid. It represents the peak of pyramid construction and happens to be the only one of the seven wonders of the world to have lasted to the present day. Khufu was the second king of the fourth dynasty. He came to throne at about 2,590 BCE. Paradoxically, we know very little about this pharaoh, of whom the only known image is this tiny ivory statuette. Khufu was the son of King Sneferu. We know from available sources that this king probably reigned for about 25 years and seems to spend all of that time building one big, massive pyramid. Khufu was the very first pharaoh to place his tomb on the Giza Plateau, an unused site, which thanks to him became the most famous in Egypt. Khufu chose the site of Giza to build his pyramid because it was a limestone quarry, supplies from which could be immediately used for the building of the Great Pyramid. Khufu's architects knew that the building their pharaoh demanded needed to be the largest ever built. To ensure its stability, they had the idea of placing the pyramid on a perfectly level gigantic slab of stone. This was a first. They wanted the foundation on the outside to be so substantial and so perfect because the previous pyramid builders had structural problems with the gigantic pyramids that came before Khufu. They had a perfectly leveled platform so the pyramid baseline in the casing would be completely stable. But to gain in efficiency, part of the massive natural rock on which the pyramid was built was left in the center of the foundations. It constitutes the first meters of the edifice's nucleus. In the middle, they left the bedrock raised up like an artificial hill. So you can see here on the northeast corner, this is bedrock, this is bedrock here, and this is still bedrock by bedrock. I mean the natural mother stone. And so is this bedrock. Here, it's almost four meters high. The base of the pyramid is a gigantic square, the sides of which are 230 meters in length, the precision of the measurements being absolutely extraordinary. It covers a total area of nearly 53,000 square meters, the equivalent of seven football pitches. The base of Khufu's pyramid is really the largest base size of any pyramid in Egypt. Thanks to this immense base and the first ever use of a 51 degree slope, the pyramid reached a previously inconceivable height. It's simply the largest ever built. It stood 146 meters high and until the medieval period remained the highest construction ever built by humankind. One might easily think that the Great Pyramid is so perfect that the blocks of limestone which make up its bulk must have been systematically cut and aligned. The reality is very different. The core of the pyramid is more sloppy. It's not brick-like squared blocks laid in brick-like masonry. You have all different quality of stone just to fill up the core. The internal blocks are hardly even square cut and the joints between them are very large. Virtually all of them were filled with mortar. The Egyptians knew they needed to be realistic. It would have been far too laborious to fill the center of the pyramid with regularly cut and assembled blocks which in any case would not have been visible when the facade was in place. When completed more than 2 million blocks of stone made up the pyramid. The building weighed 5 million tons or nearly 500 times the Eiffel Tower. Head-spinning figures. And to round off the masterpiece the interior of the Great Pyramid needed to be as impressive as the exterior. In the case of Khufu it is simply amazing. The interior of Khufu's pyramid is magical. It is a triumph of architecture and engineering. It's really a phenomenal series of spaces that must have been conceived by a master architect. In all the other pyramids the burial chambers had been placed underground or at ground level. Here the main one the King's Chamber is placed at the heart of the monument at a height of nearly 40 meters. To reach it Khufu's architects built the only known ascending corridor in any Egyptian pyramid the Grand Gallery. The Grand Gallery is one of the most awesome actually spaces ever created by humankind. It really does make you think of rising up into the sky and becoming one with the stars. This structure speaks for itself. You just need to touch the walls and look at the joints which are of an absolutely extraordinary finesse. It's a type of perfection. Over almost 50 meters the heavy stone beams of the corbel arch this time are positioned laterally following the slope of the corridor. An enormous technical challenge. You have this corbeling developed by Khufu's father in his pyramids at Dahshur but here they've taken the corbel chamber and they have it up at 26 degrees slope making it even more amazing. However, the principal purpose of this Grand Gallery was not aesthetic but completely practical. It was intended for stocking the blocking stones which would be used to cut off the access to the king's chamber. There were wooden logs put across to hold the blocks the plugging blocks. When they wanted to close the pyramid they released the brake logs and boom, boom all these blocks would slide down into the ascending passage and plug it. At the end of this majestic corridor you come to the king's chamber. An incredible cube made entirely out of pink granite one of the heaviest stones in Egypt. The whole thing weighs more than 3,000 tons. So the ceiling is amazing because it is roofed by these granite beams each one of them may weigh somewhere between 40 to 60 tons and this is the first time they roofed a space this wide. It's more than five meters. It is the only example of a flat ceiling inside a pyramid. Recent studies have shown that another unknown cavity could still be hidden inside the pyramid opening the possibility for new spectacular discoveries concerning this exceptional building. You will have many things to discover about how they made it in generations to come. The pyramid of Khufu still hasn't revealed all its secrets. After centuries of study we now know many things about these incredible pyramids but many of their mysteries remain unsolved. Will it one day be possible to know everything about these monuments which have fascinated humanity for more than four millennia? The pharaohs and their architects took their response to this enigma with them to their graves.