Dara O Briain’s new series Mysteries Of The Pyramids  starts on Channel 5 on Monday, looking at how the landmarks were built and what their true function was… and even transforming into a mummy along the way.

Here he talks about the show:  

What do the pyramids signify?

They are an astonishing human achievement and the Great Pyramid at Giza is one of the most precisely engineered buildings of the ancient world, so precise that it is even more accurately engineered than many modern buildings, which is an incredible statistic after 4,000 years. 

What’s remarkable is the Egyptians were able and willing to build them, and then, after a little over a century, stopped building them at such a grand scale because ultimately the great pyramids failed in one of their most important tasks: to protect the Pharaoh and his possessions from tomb raiders.  

The ancient Egyptians had the sense to realise it wasn’t smart to continue building pyramids and there was an opportunity cost which was bad for their society. Instead, they decided to make the tombs richer and more ornate and deep underground.

How tempting were these tombs for thieves?

What we explore in this series is a game between tomb builders and tomb raiders; they were breaking into pyramids, so the builders began to create more and more elaborate anti theft devices in their pyramids such as long dark labyrinthine passages, heavy rocks blocking entrances.

But no matter what they designed, the tomb raiders always got in - obviously - to steal the tombs’ contents. Those thefts were probably an inside job. 

We had a view that tomb raiding was very Raiders Of The Lost Ark or down to expeditions like Lord Carnarvon’s, all taking place much later. [But]  many of them were broken into far sooner.

What were the risks for tomb raiders?

There are records of punishments and it wasn’t a slap on the wrist. The method of death was swift and exemplary, from the genre of Game of Thrones gruesome deaths: Impaling the captured tomb raider was a favourite.

How does the Great Pyramid dominate Cairo?

There are other sites in Egypt which are equally beautiful but there’s nobody there, so you ask yourself why people flock to Giza. There’s a touch of the Mona Lisa effect - everyone piles into Giza because the pyramids are so iconic. The Great Pyramid the last surviving wonder of the ancient world.

Do you get the sense of what the view would have been more than 4,000 years ago?

To preserve the globally iconic vista of the pyramids a corridor of desert has been kept behind them, which is incredibly difficult to do when you have a city of almost 25 million people encroaching on the site.

What people are being sold at these sites is the Victorians’ view of Egypt.

How different was your trip to a tourist’s?

We were able to access the pyramid by ourselves, which was incredible. Giza is a messy site, full of tour buses and tourists on bucket list trips piling into the sights. You see the tourists emerge from the Great Pyramid all frazzled, because they have to climb the central passage stairs at the same time other visitors are descending them.

These tourists have dreamed of visiting this place for ages and it’s all a rush. Giza is an amazing place, but it’s also a magnet for crazy and idiotic things.

As a scientific-minded person, what do you make of the exotic theories around the pyramids’ construction and purpose?

Some people have fun with them and it can be very lucrative for some people to fudge things, but the theories are stupid. They are really silly theories. 

The pyramids are stones on top of other stones; the construction was an amazing administrative job, an epic effort, and an incredible engineering achievement. 

When we were making the documentary, we saw how an ancient tributary of the Nile brought the massive stones much nearer to the pyramids than would be possible today. How the stones were carved, and the camp which housed the tens of thousands of people who worked there.

What’s most intriguing is the will and the devotion to the Pharaoh to construct these monuments 4,500 years ago. If you went inside the pyramids and there was a massive vaulted ceiling, a waterslide, and a merry-go-round, then you’d concede the construction was suspiciously clever.

A pyramid is the shape you build when you don’t know how to build arches or cantilevers, which is why it’s repeated across the globe. 

On our last day we left the Valley of the Kings to visit Luxor, which was built 1,000 to 1,500 years later, and you can see how techniques had evolved. The carvings are astonishingly ornate, the pillars are curved and regular, there are arches, and there’s a two-mile walk of sphinxes. The Egyptians just became even better builders.

Did you find the speculation aliens are behind the pyramids annoying?

I grow increasingly irritated with the argument aliens must be involved in ancient monumental building, not so much just because of the pyramids in Egypt, but a site far closer to home. Newgrange in Ireland is a huge Neolithic burial tomb, 700 years older than the pyramids, and was built so that on every winter solstice light enters through a gap in the wall and creeps along a passageway.

We’re deeply proud of Newgrange and there’s a ticket lottery for places inside the tomb on the solstice to watch this magical event. If you were to say to us, ‘The Irish couldn’t have built that, you probably needed aliens,’ you would rightly get a slap.

What are we doing to history by giving aliens the credit for these structures?

My huge problem with all this is you ignore a really interesting human constant; we revered figures, we looked for a greater meaning, and we worked to build monuments which towered over us. To give aliens the credit removes the appreciation of how these societies constructed these monuments. 

Why would you deny yourself the knowledge of how they built these structures with such amazing skill and imagination?

Also, if aliens were responsible, where were they when we wanted to fly? Where were the aliens when Europeans wanted to build cathedrals? They were very quiet on those occasions.

If pyramids aren’t alien galactic mapping devices, what are they?

When you stand in front of them they are, very clearly, a giant monument. The ancient Egyptians venerated the Pharaoh and had a belief system which said the king would be transported to the afterlife. Cathedrals have essentially the same purpose, but I don’t remember aliens being given credit for them.

What’s amazing is noticing the evolution and improvement of the tombs, and how they reacted when Tutankhamumn died unexpectedly. Rather than carve the inside of the tomb they painted it, because they’d been caught out by his early death. There’s a lot of humanity inside these tombs.

What sort of evidence is there of the construction workers?

In the third and smallest pyramid at Giza, which is dedicated to the Pharoah Menkaure, you can see graffiti scribbled onto the wall by a crew that says, ‘Drunkards of Menkaure’ It’s thought a crew would be a group of 150 to 200 men who worked in shifts, moving and cutting the stones. Then, afterwards, they’d eat and get hammered - like working people do! These were well-fed people, not slaves, living their lives.

The humanity of the work shines out. We crawled inside the pyramid and saw bits of pottery lying around – but we didn’t nick any of it!

Given pyramids were religious shrines dedicated to a pharaoh, wasn’t it dangerous to graffiti the inside?

There probably shouldn't be an empty can of Diet Coke and a copy of The Sun hidden within the walls of my bathroom but I know there is, because every plasterer and plumber sticks their soft drink can and their paper in the walls. We’ve all renovated a room years later and said, ‘What the hell is this?’ when we’ve found stuff lads have left behind.

If you look at it in those terms, it makes perfect sense.

How did you find coming face-to-face with Tutankhamun?

We visited Tutankhamun’s tomb and were allowed to go down some steps into his tomb, which made all the tourists furious. His tomb is really small, relative to other ones we visited, and they banged it together quickly.

When you walk into his tomb the big sarcophagus is on one side and on the other is a climate-controlled glass box with a mummy inside. And that’s him - he’s been returned to within 12 feet from his eternal resting place. The death mask is an astonishing piece of work to see close up.

Is there a particular reason why his tomb wasn’t robbed?

Tutankhamun was only a kid when he died and his tomb wasn’t robbed because it was more of an afterthought than a major one. 

The interior is painted rather than carved and it only has three rooms; Seti’s tomb, also in the Valley of the Kings, has huge corridors and would have been filled to the brim with even more treasure’s than Tutankhamun’s tomb.

Perhaps the tomb was well hidden, or people forgot about it, and those are possible reasons why it survived for so long… thousands of years before finally being discovered in the early 20th Century. 

Ironically, as a result, Tutankhamun and his death mask have become the icon of ancient Egypt.

Before this series how aware were you of pyramids existing in multiple civilizations?

25 years ago I went to Teotihuacán, which is outside of Mexico City, and I’ve also been to Chichen Itza, as well as various sites of the Aztec and Inca world. More recently I’ve visited Borobudur in Indonesia, which is a very ornate Buddhist temple.

I’ve also seen pyramids being built in the spare room by the kids using Lego, which holds together better than big lumps of stone.

Are they any major tombs left to find?

The big figure yet to be discovered is Nefertiti. It’s thought a whole new museum would have to be opened if Nefertiti’s tomb was discovered. She was queen of Egypt roughly 3,500 years ago. She’s a genuinely major figure, so the game is on and there are still Lord Carnarvons and Howard Carters out there funding trips and exploring.

How thrilling do you find the efforts to unlock these ancient secrets driving modern scientific breakthroughs?

It doesn’t take a great deal to get me excited about the scientific aspect, because I’m not a historian and I’m in my usual role of being the guy asking the smarter people questions. That's one of the two corners I’ve carved out for myself - handing out points and asking the smarter people questions.

I did get stupidly excited one morning about particle physics. Amidst all the history, there was talk of a Boson particle detector which is used like an X-ray to show shapes inside a structure. I became really excited and wanted to know all about the particles and how they react with other particles.

What blew your mind most during filming?

It's hard to get past the scale of the pyramids. Cairo is an insane city, throbbing with over 23million people, but at one point you turn a corner and there they are.

As with any iconic landmark or work, to see them up close when you’ve seen them so often at distance is incredible. We went to film inside at night after the site had been cleared and I took a photo of the exterior of the pyramid with Orion above it, which was lovely.

The Indiana Jones part of filming was fun, when we were scrabbling around inside a pyramid at night with nobody else around.

Are you good with confined spaces?

I'm slightly claustrophobic and I'd feared how big the spaces would be, but it was fine. You have to stoop and crawl a lot, and I was happy to crawl for the Pharaohs.

• Mysteries Of The Pyramids with Dara Ó Briain is on Channel 5 at 9pm on Monday