Saudi Arabia Built a $16BN Clock Tower

Video narrated and hosted by Fred Mills. This video and article contain paid promotion for Masterworks.

This video depicts a different on-site health and safety and labour culture to the one that many of our viewers will be familiar with and that we at The B1M advocate for. We acknowledge this, and have made the editorial decision to bring you the footage to tell the extraordinary engineering story of this project.

THE MAKKAH Royal Clock Tower is a triumph of engineering. At 35 times the size of Big Ben it has the world’s largest clock. Constructed at an estimated cost of USD $16BN it is one of the most expensive buildings ever constructed, and at 600 metres high it contains to this day the highest occupied man-made space in the world.

Seeing the tower rise above the city of Mecca it’s hard to get a true sense of its unbelievable scale.

Construction firms from over ten different countries worked on the skyscraper, including a German firm which designed the clock. But because of its location in Mecca many of the engineers and architects could not visit the site.

After all, only Muslims are allowed in the sacred city.

Above: The clock face is the largest in the world, 35 times that of Big Ben. Image courtesy of SL Rasch.

Speaking exclusively to The B1M, Mustafa Rasch, CEO of SL Rasch and former site manager of the Makkah Royal Clock Tower explained: “So Mecca is very conservative. Saudi Arabia at the time already was very conservative, and Mecca there is still a border before you enter the city. It's like a border going into another country. There's a passport control.”

Some of the construction team, including glazing experts from Poland and Germany, converted to Islam so they could work on the project.

“The company RIVA, near Stuttgart in Germany, and their owner is one of the people who actually converted. He converted to Islam during that project to be able to come on site and see for himself what's going on and what's happening.”

“His whole installation team there were Polish, [they were] glazing abseilers hanging on ropes and putting the glass in as a team of eight people. And they also converted.”

Welcome to Mecca

The Makkah Royal Clock Tower isn’t just a hotel, it can’t be. It’s located in the heart of one of the most culturally significant cities in the world.

Every year up to 3M Muslims travel to Mecca to complete a pilgrimage known as the Hajj.

Those completing the Hajj circle around the Ka'bah seven times. It’s an ancient ritual that every Muslim must complete at least once in their life.

This site is thousands of years old, extremely delicate, and constantly crowded. And just a few hundred metres away, across the road, is where this enormous hotel was to be built.

This is far from a simple construction site.

Above: The tower is located right in the heart of Mecca.

“It's right in the centre of Mecca City,” explained Rasch. “You know, inside the first ring road, which is really the most congested area in Saudi Arabia, then the centre of Islam. All Muslims want to go there. You have the Holy Mosque with the Ka'bah in the middle and right opposite.”

The religious tourism market is the second largest source of income for Saudi Arabia after hydrocarbons. It contributes some $12BN annually to the kingdom’s economy.

This means that Mecca has the largest number of hotel rooms in the Arab World, far surpassing Dubai.

It really then comes as no surprise that this enormous hotel would be constructed here.

More than just a hotel

“Due to the nature of it sitting so closely to the Ka'bah and in this very, let's say, sensitive environment, the client reached out to us and wanted to elaborate with us ideas on bringing more meaning to the building.”

The hotel needed to be more than just a commercial building, because of its location. It needed to be something spiritual.

“We started thinking about what such a building could stand for. And then one of the ideas that was created in those several meetings and brainstorming was that the main tower tower could function as the minaret of Mecca. It was planned and would have been the highest building in the world.”

The hotel was originally supposed to be only 450 metres high - which would have still made it the tallest building in the world at the beginning of its construction in 2002.

Upon deciding to transform it into a grand minaret the height was then extended to 600 metres.

“Burj Khalifa was not built yet. It was also in planning and they, of course, once it was clear that this tower would be 600 metres, they raised theirs to 800 metres and took the record for that one.”

But making this hotel into an enormous minaret wasn’t enough. The client wanted even more.

The world’s tallest clock tower

“Of course, timekeeping is essential. There's five prayers during the day in Islam, and they all happen to a certain time.”

Time plays an important role in Islam. There is, of course, the call to prayer that happens five times a day. The Athan is the first call to prayer and is usually made from the top of a minaret.

The idea of then making this building into a clock tower as well came very naturally.

Above: The enormous clock face. Image courtesy of SL Rasch.

This clock would establish a new second time standard in addition to Greenwich Mean Time. All over the world Muslims would be able to know the precise atomic time in Mecca.

This would allow Muslims to begin holidays and special occasions like Ramadan simultaneously, regardless of where they are on earth.

There was just one huge problem: half of the building was already built.

Tall… but light

By the time the Saudi’s wanted to extend the height and add the clock tower, half of the hotel was completed.

This meant the foundations were well and truly laid into the ground and had been designed to accommodate a 450 metre high skyscraper above them, not a 600 metre one.

This limited the weight of the building to just 82,000 tonnes.

For contrast, Shanghai Tower - which rises to a comparable 632 metres - weighs 575,000 tonnes.

“So we went into checking the foundations. How were the foundations laid out? How were they calculated? What forces were they allowed to hold? And we saw that they have a lot of reserves. And that's the typical measure in Mecca that all the buildings have a lot of reserves, just for the sheer fact that there are so many people moving through the city and they want to be on the opposite side. We started developing, then an ultra lightweight structure that could be placed on top of this concrete tower.”

The engineers and designers needed to create a tall, lightweight, but strong structure to put on top of the existing hotel.

Fortunately, history had already solved this problem.

Rewind the clock to 1889 and Gustave Eiffel was planning to build the tallest manmade structure in time for the World’s Fair.

To build it high and fast - and to ensure it didn’t sink under its own weight - he came up with the now iconic wrought iron framework structure.

This allowed the tower to soar to new heights and redistributed its weight downwards to its base.

The engineers of the clock tower began sketching their design by placing the Eiffel Tower on top of the existing hotel.

Above: Engineers took inspiration from the Eiffel Tower by placing it on top of the enormous hotel and building their clock around it. Image courtesy of SL Rasch.

They used high-strength steel and concrete instead of wrought iron but kept the idea of a framework structure that grew more slender as it rose, like the trunk of a tree, and kept the same engineering principles from the Eiffel Tower.

They would then build their clock and minaret around that framework structure.

This lightweight structure was then placed on five transfer slabs on the top of the hotel.

There were of course a number of limitations that came with this approach, the distance between floors, for example, had to be far higher than normal.

“I mean, behind the clock, one floor level is about 12 metres. You could not go with typical floors, the weight would have been exceeded. And then also the floors are cut out. There’s a big void in those floors.”

The voids, which made the floors weigh less, were then incorporated into the design and used to display large exhibits and artworks.

“So it works well with the exhibition, but that was actually all the reason to reduce the weight of the building.”

A clock 35 times larger than Big Ben

With the structure worked out it was time to turn their attention to building the world’s biggest clock.

The architects of the tower worked with Perrot, a German company that had been designing clocks since 1860.

“There were a lot of different design iterations that went into the clock mechanism, the clock hands. How do you operate such a big clock, especially in that high?”

“The clock hands were one of the biggest challenges,” added Stefano Delisi, the facade architect for the tower.

Above: One of the four faces of the clock tower being constructed. Image courtesy of SL Rasch.

Because of the size of the clock and its immense height, the first challenge was figuring out how to keep the hands from blowing away in the wind.

A number of designs were considered, including having the tips of the hands guided by a peripheral track. Similar to how a Ferris wheel works, or a rollercoaster.

Unfortunately it was discovered that this idea would be too heavy. It also had too many moving parts that could malfunction and would eventually need replacing. You would also see the track underneath, ruining the facade.

“But we didn't like the idea of having a slit, a circular slit around the facade,” Delisi continued.

They needed something lightweight and simple.

Hands so big you can walk inside them

It was decided the hands would be made of carbon fibre and they would be controlled by a centrally installed clock drive that could hold both of them.

The hands themselves measure 23 metres and 17 metres respectively. For comparison Big Ben’s hands are 4.2 metres and 2.7 metres.

“With a fantastic team of engineers we found out that we could use a special carbon fibre to make this clock and cantilever it. So we have this 23 meter long clock which is completely cantilevered. Of course they have counterweights on the other end to balance.”

Above: The clock hands were so huge, people can walk inside them. Image courtesy of SL Rasch.

“The wind pressure on this gigantic clock face was also tremendous, not just on the hands, but also on the facade,” explained Günther Schnell, another architect on the project and the former Head of Special Structures at SL Rasch.

The clock face was designed to be slightly concave to shield the hands from the wind, which at this height could reach up to 200 kilometres an hour.

“The concavity of the clock was in order to keep the clock hands within the profile of the building and not to have outside the building profile, so that's why you have this,” added Delisi.

“There are four clock drives, actually five. The fifth one was also put up on the platform floor as a spare,” explained Schnell.

“And we also have a spare set of clock hands. They are so big that you can actually access them and walk in them. At least it can be done quite easily. You don't have to build a scaffolding that goes 500 metres high.”

Lighting a megatall

The designers conducted a number of tests to figure out the colours of the clock. It was especially important to work out how it should be lit up at night so it could be the most legible.

“The obvious idea: let's backlight the facade. But that was directly dismissed because you would lose definition of the architectural details,” said Delisi.

After several trial runs under different weather conditions and with different colour combinations it was decided that instead of black and white the clock face would be green and white and that LED lights would be used.

Above: Green was chosen to light the clock face. Below: Workers fitting the millions of LED panels. Images courtesy of SL Rasch.

Green and white was chosen because of how the human eye works. When green light refracts in the eye it focuses on the image plane of the retina, creating a sharper image.

These colour combinations would ensure the clock face could be seen clearly from more than 8 kilometres away.

LED lights would illuminate the clock face. Each LED pixel was installed 105 millimetres from the next one so that from a distance it would appear as a single green surface.

More than 2M LEDs would illuminate the tower in total.

“These LED lights were also specifically developed for the task,” explained Schnell. “And we took about a year, I think, till we finally were happy with the outcome. The problem is that if these LEDs get very hot, their lifetime is reduced dramatically and we have a hot climate.

“The problem was to find the right casting as a cooling body for the individual LEDS. But somehow they seem to last quite well. So we are happy with that.”

More than 98M tiles

Keeping with Islamic traditions, the facade of the tower is covered in 98M mosaic tiles each measuring 20 by 20 millimetres. The glass tiles came in 13 different colours, one-third of which contain 24 carat gold leaf.

The order for the tiles was so immense that the Venetian company producing them had to invent a new way to automate the process just so it could get done.

Above: The glass "jewel" of the minaret. Image courtesy of SL Rasch.

“This is a very good company that was chosen for their quality,” said ​​Delisi. “But at that time, the particular gold tiles were manufacturing an amount of 15 to 20 square metres a month. And, we were in need of a 250, 300 square metres a month to catch up with the construction.

“We developed with them a robotic system.”

The tiles themselves had to be rigorously tested to ensure they would withstand the extreme weather at the top of the building.

“Everything has been tested in lab, also physically, weather, outside and fire tests and all the possible tests were made.”

Made in Dubai

Much of the tower was prefabricated in Dubai - a city that knows a thing or two about megastructures.

The 98M tiles were sent here and put on the facade piece by piece all by hand. More than 100 men worked on the mosaics and only the best, most flawless tiles were selected.

These finished pieces of the facade were then broken down and taken across the desert in trucks in a three day journey to Mecca where they were reassembled.

The clock face itself was also built in Dubai first so they could see what it would look like first hand.

This was done partly to test the structure, but also because many of the architects and engineers working on the building could not travel to Mecca themselves to see it finished. This allowed them to make any necessary adjustments.

Above: The construction process involved tens of thousands of labourers. Image courtesy of SL Rasch.

“We had the test ground in Dubai. We had to erect a quarter of the clock. Complete full. And, so we had to rebuild the main structure.”

It too was then dismantled and sent to Mecca.

The very top of the tower was also pre-fabricated in Dubai. This crescent-moon shaped structure would reach for the sky and house the highest prayer room in the world.

“The crescent bit is a half moon. That is a typical element that is put on top of the minaret. And this identifies the building as a minaret.”

“The crescent itself is the biggest, carbon fibre structure ever built,” added Rasch.

It contains three floors with the prayer room, a meeting, and an office.

The highest prayer room in the world

Finally the time came to lift the prayer room to its place at the top. It had been severed into several parts so it could be trucked to Mecca. There was just one problem. Where the prayer room was to be lifted was so high, the crane could not reach it.

“There's a spiral stair that goes through the spine of the crescent,” explained Rasch.

“And, a friend of mine and myself, we always went up that spiral stair to take a break, went there to smoke a cigarette. And it was beautiful. You know, you sit. There's nothing around you.

“And we knew, okay, from the program that the Crescent will come in within the next two weeks.

“And then we looked on the tower and said, it's a bit weird that the tower crane was only then reaching with the tip kind of that platform.”

With very limited time left they had to raise the crane to its absolute limit.

Above and Below: The tower crane was raised to its absolute limit. Images courtesy of SL Rasch.

“The tower crane was then at a height of 220 plus metres and, then quite a heavy load on it. The one segment of this crescent was seven, 7 to 8 tonnes.

“The capacity of the crane got to its limit because of the height, I mean, everything was at that limit. The height was just enough. The capacity, the weight of the crescent was exactly on the limit of the crane.”

Then came the wind.

600 metres above the ground riggers strapped into harnesses, some on the structure, others on the tower braced themselves against incredibly strong winds.

The crescent soon began spinning out of control.

Above: The crescent itself is the largest carbon fibre structure in the world. Image courtesy of SL Rasch.

“Yeah, I think or 2 or 3 guys that really got sick. They just got sick. Because it was rotating.”

The men on the viewing platform had to use ropes to steady the structure and bring it into place.

“The poor crane driver, I think he was going nuts because on the walkie talkie and people from down were yelling at him. But they managed, it took quite a while longer than anticipated.”

With the prayer room in place the tower was topped out.

An icon completed

To this day it is still the highest occupied space on any manmade structure.

The Burj Khalifa’s highest occupied floor is at 585 metres, while Shanghai Tower’s is 583 metres. Both pale in comparison to the prayer room 600 metres above Mecca.

“Then we had the opening ceremony where the king actually came to Mecca, and he pressed the button to turn on the lights.

“And that was a great moment. That was really, really good. I mean, it's like three years of hard core pressure and stress and it all came to a success.

“It was a great moment, one of the best moments in my life, that's for sure.”

The clock tower now stands as a symbol of Mecca in the 21st century. A place steeped in history with an important role in millions of people’s lives today.

Above: The tower rising on the Mecca skyline. Image courtesy of SL Rasch.

There isn’t another building like it, and there probably never will be again.

“I think it's totally different from any other, even the most spectacular of buildings of extreme height. They will never compete with this shape and this function,” said Schnell.

“It's the only tower that gives its own time signal. There is a time signal now available for all Muslims worldwide.

“Anything which is for unification purposes these days is good.

“I think that's very important and that maybe the real value of this structure.”

The forgotten megatall skyscraper

Despite shattering so many records, the building is little known in the Western world.

“At the beginning, I was a little bit disappointed,” admitted Delisi.

“I managed to understand that maybe even it’s a good thing for the building because you have in contemporary architecture, the building is not even finished and it is already on the magazine or on the internet. People talk for one month and then it is forgotten. So I assume this building is really slowly metabolised by the city, is becoming an icon, and slowly, slowly will become, in time, an essential building.”

“I think that the building in itself will remain an icon for Saudi and it will remain an icon for the whole Islamic world, because, of course, many Muslims have worked on the building,” added Rasch.

Above: The construction team consisted of workers from all over the world. Image courtesy of SL Rasch.

“There were at times up to 15,000, 17,000 construction workers on that complex, all of them Muslim and all from different countries all over the world. So pretty much every country has a story, a connection to that building which you do not have in typical buildings.

“But it's not about the biggest clock, for me personally, it's not that important,” said Delisi. “This big clock has offered this opportunity to explore materials, technologies, new spaces. So it's a completely different building than just a stereotypical skyscraper.”

Despite working on the project for several years, many of the lead architects have never seen the building in real life.

“Oh no, I couldn't. So I hopefully I will do one day.

“There is one thing an architect can do. They can imagine quite well. So it’s been in my head for four years of my life.

“Of course, to stand there, look and walk around would be fantastic. But in my head it is quite well represented and imagined.”

“I can say that I didn't convert,” Schnell said when asked if he’d ever seen the tower in person.

“The closest I ever got physically was, I think, 20 kilometres, which is already inside the confines of Mecca, because my driver didn't realise that he had a nonbeliever on board.

“He stopped in the middle of the motorway and made a U-turn and drove me back out again.

“I mean, this building is so gigantic and you can see it from 50 miles away or even further.”

We’re now seeing so many new projects being announced in Saudi Arabia, from giant linear cities to desert arenas, all with fresh scepticism as to whether they can be achieved.

And while that still remains to be seen, the Makkah Royal Clock Tower is in many ways the first Saudi megaproject. Whatever comes next it remains a towering accomplishment in its own right and will in all likelihood stand the test of time.

This video and article contain paid promotion for Masterworks.

Video narrated and hosted by Fred Mills. Additional footage and images courtesy of SL Rasch. Special thanks to SL Rasch.

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The Makkah Royal Clock Tower was designed and engineered by SL Rasch GmbH - https://www.sl-rasch.com/en/