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Obelisk at Amun Temple, Karnak, Luxor. Source:  Andrej / Adobe Stock.

How Did They Do it? New Insights on the Ancient Obelisk Transportation Mystery

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In the golden sands of ancient Egypt, behemoth stone structures known as obelisks have stood the test of time, narrating tales of a civilization's grandeur and prowess. These magnificent structures pose a tantalizing question that has puzzled historians and archaeologists alike: how were these colossal monoliths transported and erected with the seemingly limited technology of the past?

Have the methods the ancient builders used been lost in the mists of time? Is it possible that in the past they could have developed brilliant ideas that we don't know about? I believe that this is not the case, that all it takes is to recover what means and methods they could have used by reflecting on our knowledge of construction methods.

Land Transportation of Obelisks

Obelisks were extracted from quarries that were generally very distant from the place where they were to be erected. Their transportation generally involved a journey by land from the quarry to a dock, where they would be loaded onto a suitable ship that would take them down the river as near as possible to the placement site. There, people disembarked the obelisk so it could be taken across a new land route to reach its final destination.

There is little information about the land transportation methods used and a little more about the river ones, but in both cases, many details are unknown. Those details are important to understand how, with the technical means they had, it was so "easy” for the ancient Egyptians to carry out these works. Before presenting my point of view about how they could do it, we are going to analyze several aspects.

The general idea that emerges from bas-reliefs and paintings is that the transportation of large monoliths was done by placing the piece on a more or less robust wooden support with ropes tied to it, which was then pulled by the amount of people necessary to drag the load.

We could think that this was the case insofar as they did not know of the wheel, but there is no evidence of the use of this method in the transportation of these large loads, nor of the use of animals for the task on a regular basis. If we consider that the wheel was not used for transportation in the construction of these obelisks, some problems arise that we will study more deeply.

The general belief is that ancient people moved large monoliths on sleds pulled by ropes. (bellass / Adobe Stock)

The general belief is that ancient people moved large monoliths on sleds pulled by ropes. (bellass / Adobe Stock)

The Staffing Problem

Surely, the routes that the obelisk would have to follow by land were flat or with gentle slopes and not excessively long. With that in mind, we can establish a gross value for the load a person could drag. If, for example, we consider this value at around 100 kg (220.46 lbs.), 2200 workers would be needed for a piece weighing 220 tons. This analysis is very simple, but it tells us that the number of people involved is so great that the force generated by the workers would have been applied through several pull lines.

If we place, for example, 20 pull lines, each one would be operated by 110 workers. Each pull line would need to achieve a force of 0.40 x 220 / 20 = 4.4 tons. That would take a 75mm (2.95 inch) rope. To be able to use it, the workers would have had to wear some type of harness that tied them to the rope, something which does not appear in graphic representations.

There are only two geometric ways to transport the obelisk by dragging.

If it is done with the piece placed longitudinally along the road, the 20 pull lines must be of the same length and use a large transport sled, which would possibly be difficult to build and handle. The transport train would occupy some 150 meters (492.13 ft) or more along the road.

The second method involves moving the obelisk by positioning it perpendicular to the direction of the road (crosswise). In this case, several smaller sledges would have to be placed, which would favor their construction and handling. The pull lines would not be the same length in this case due to the variable weight across the stone. The space occupied by the transport train would now be variable, but the maximum distance would still be around 150 meters (492.13 ft).

In both cases, the width occupied by the transport would be greater than 20 meters (65.62 ft). Consequently, the track where the obelisk is going to travel would have to be that width as well. The transportation tracks that are preserved reached remarkable widths. The road would need to be clean, free of obstacles and regularized. The possibility of using this system to extract the obelisk from the excavation in the quarry is completely null.

The Sled-Carriage Problem

The only graphical representation of this type of massive load transportation is the one found in the tomb of Prince Djehutihotep, where a large statue can be seen on a cart-sledge pulled by several lines of workers. Regardless of the reliability of the number of people depicted pulling the statue, what is interesting in the representation is the robustness of the sleigh-cart. It is evident that this must be the case since it is the element that supports the pulling forces, and also has to withstand the efforts derived from changes in direction and, in addition to that, has to transmit moderate contact tension with the ground to allow it to slide.

Schematic drawing of the transportation scene of the colossal statue of Djehutihotep. (Public Domain)

Schematic drawing of the transportation scene of the colossal statue of Djehutihotep. (Public Domain)

It would take some pretty big trees to make two (or maybe more) stringers to support the obelisk in one piece. Surely two or more parts would have to be assembled for each one, which would mean the weakening of the piece. The crossbar assemblies would be highly stressed when changing direction. These assembly efforts could have been very important in the ship loading and unloading processes.

We can make a comparison with what could have been the transport sled of a standard block of the body of the Great Pyramid. As it was an element with almost the same geometry in both directions, changes in trajectory did not present as many problems to its structure. The construction of the sled is therefore a major problem.

Blocks at the Great Pyramid of Giza, Egypt. (CPQ / Adobe Stock)

Blocks at the Great Pyramid of Giza, Egypt. (CPQ / Adobe Stock)

Problems with Changing Direction

To change the trajectory, in the event that the transport is carried out longitudinally, it is necessary to generate very important transverse forces simultaneously with the pulling forces that would generate very notable efforts in the transport sled-carriage.

It could have been difficult to take sharp turns, which might have been necessary on the approach to the loading dock. Even approaching the piece to the edge of it could be impossible. The 20-load line rigging needs elements to maintain the separation between the lines with some type of yoke that supports the compression of the changes made on the ropes, greatly complicating the operation.

Therefore, we can see that even though it is possible to use such a system, with its excessive length, its rigidity and the need to resolve changes in trajectory, there would be several downsides to this method of obelisk transport.

It is evident through these three problems, and perhaps others, that there are serious doubts about the use of the exposed drag method. Perhaps the system represented in the tomb of Djehutihotep is mistakenly generalized as a common practice in the past.

A More Appropriate Form of Obelisk Transportation

The application of this mode of transport to an object other than the aforementioned statue does not seem to be the best option. The transport train needs a smaller area of occupied space so that the piece can be handled in the quarry and changes in direction can be made along the way while bringing the piece closer to the transport ship for loading.

Unfinished obelisk, Aswan, Egypt. (Abraham Moral Toro / Adobe Stock)

Unfinished obelisk, Aswan, Egypt. (Abraham Moral Toro / Adobe Stock)

It would have been more logical to transport the piece not longitudinally but crosswise to the road. Sledges placed perpendicularly to the piece would be more suitable when applying the transport forces and would completely solve the problem of how to load and unload the monoliths on the ship. The obelisk would be placed on several sledges with relatively short stringers. For these sledges it would be easier to achieve the robustness required by the efforts arising from special transport situations. It could be easier to solve two problems mentioned above: the transportation cart and the ease of movement at turns.

Even so, the problem of loading the ships is still difficult to solve once the piece arrives at the river dock. It seems that there must have been some system that facilitated loading and unloading maneuvers, through the introduction of adequate forces. Much has been discussed about how the loading and unloading was done. One proposal is the use of canals in which boats would be placed and, when rising with the river flood, people would load the obelisk, and other more or less ingenious systems; but all of these hypotheses involve positioning the piece with a train of workers, which could not work in most cases.

The fundamental problem lies in analyzing whether there could be an alternative to the human traction force with that technology, which could have been used and which would have solved the situations of loading and unloading the ship in addition to those of transportation. So, we will analyze a way of generating traction forces that emerges from the very foundation of the ropes.

Generation of Tensile Forces

In order for a rope to be used as a drag line, a force needs to be applied to it. This force can be generated by a person or several people pulling on it, or by a weight hanging from it. However, this procedure is not suitable for pulling heavy loads.

There is another way to apply force and that is to get the rope to deform, like for example, when using a tensioner. Ropes can handle high and variable deformations, and therefore, the procedure of introducing the deformation must be safe to ensure that the force needed can be developed. The best way to produce such large deformations is by twisting the rope.

To achieve this, two ropes are tied to two fixed anchor points, which in turn are located on a support that we will call the Fixed Point. The other end of the ropes is tied to a sled with a load we want to transport.

Forces are developed in the ropes by twisting one with the other. A helix is then formed, which lengthens the ropes. Depending on the state of the rope, it could be necessary to twist it several times until it begins to deform enough to properly generate force.

The ropes are wound into a helix with a diameter similar to that of the ropes themselves. Each time a turn is made, with the distance between the end points being constant, the rope has to lengthen in order to wind around the cylinder. Eventually, it comes to a point where the elongation generates a force capable of dragging the sled with its load.

When this happens, the following turns will drag the sled with its load further towards the Fixed Point. The number of turns that can be made will depend on the diameter of the rope and its length. When the pitch of the helix is too small or the force required to make another twist is too great, the ropes, which were anchored to the Fixed Point, are unleashed. All the deformation is then recovered, and we can proceed to another cycle.

Fixed points, ropes, and sleds with their load. (Author provided)

Fixed points, ropes, and sleds with their load. (Author provided)

A design of the Fixed Point and diameter of the ropes to be used can develop a limited amount of tensile force. If more force is needed, as many parallel lines as needed can be positioned and it is also possible to adapt the geometry of the object acting as the Fixed Point.

The Fixed Point needs to be stable for both overturning and sliding. Tipping can be easily prevented. The rope will be as low as possible, and it will be given enough length to balance the movement with a small counterweight. However, slippage could be a problem somewhat more complicated to solve. The terrain that makes up the path may vary between rock and any thickness of granular material. The Fixed Point should be supported by a reaction Wall, which can be made of wood and embedded into the ground.

The tool that allows for twisting is made of a suitable piece, with two levers that minimize the risk for the workers using it, since high forces are developed and can be very dangerous. Depending on the dimensions of the system, one worker on each lever could develop sufficiently high forces.

Tool and torque levers. (Author provided)

Tool and torque levers. (Author provided)

Once the lines have been assembled, the twisting process begins. After a few turns, the force necessary for pulling will be generated. Successive turns bring the load closer to the Fixed Point.

Twisting the ropes. (Author provided)

Twisting the ropes. (Author provided)

This system allows the extraction of the obelisk from the quarry, the transportation of the load from the quarry to a loading dock and the loading and unloading of the transport ships.

The process described above underscores a robust solution for transporting large stone blocks, easily, including long ones, by using enough pull lines. This method works well even on downhill roads as long as they aren't too steep. Changing direction when there is a wide curve in the road is straightforward; all you need to do is pull harder on one side than the other. The sledges used for moving the stones can be built strongly enough to handle the forces they meet during turns if the ground isn't too uneven. This strategy also makes it simple to load and unload boats by moving a fixed point over to the boat's center. Furthermore, moving heavy objects like obelisks to specific spots, such as in front of a temple, is also made easier using this method.

This investigation offers new possibilities on the enduring mystery of how ancient Egyptians transported mammoth obelisks. It offers a fresh perspective, and encourages a deeper analysis of historical engineering marvels.

Top Image Obelisk at Amun Temple, Karnak, Luxor. Source:  Andrej / Adobe Stock.

By Jacinto de la Riva Gómez

 

Comments

The logistics of Ancient Egyptian mega-construction are mind-boggling. Cutting, facing, transporting and erecting or positioning one massive stone block is a feat that would require effort beyond the imagining of many today. Yet, when one considers just how much stone was involved, none of it seems possible.

Jacinto De La Riva Gómez's picture

Jacinto

Jacinto De La Riva Gómez is a Civil Engineer specialized in structures and Highway Projects with extensive experience in the world of construction. He has a particular interest in how massive construction projects were undertaken in ancient times, and how... Read More

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