The incredible Egyptian pyramids are one of the greatest ancient wonders of the world. Dating back more than 4,600 years, the fact that they are still standing today is a testament to the power of their construction.

How the pyramids were built is the world’s oldest puzzle and many highly educated scholars gave many controversial theories and hypotheses. the most generally believed theory is that the massive limestone blocks were carved from the quarries in Giza using copper and bronze chisels, then dragged and lifted into the accurate position. The manner of the movement and placement of these stones blocks and the size of the workforce are under great debate even today.

Archaeologists, engineers and historians have marveled at the ingenuity of these timeless structures and the mysteries about how exactly they were made. One of the most asked questions is, how long did it take for the Egyptians to build these epic monuments that have lasted throughout the centuries?

How Long Did It Take to Build the Pyramids?

The short truth is, no one really knows how long the Egyptian Pyramids took to build, because they are so old, and such little evidence survives from the time when they were made. But estimates suggest each pyramid could have taken somewhere between 15-30 years to complete. Around 118 different pyramids all across Egypt have been identified.

The oldest in existence is the Pyramid of Djoser near Cairo, while the largest and best known is the Great Pyramid of Giza in the Giza Pyramid Complex – depending on its size and shape, and when it was built, each one presented its own challenges and timescales for completion.

The Egyptian Pyramid of Djoser Might Have Taken 30 Years to Build

Estimates by Egyptologists suggest the Pyramid of Djoser, also known as the Saqqara Step Pyramid, took around 20 years to build. It had six layers, one on top of the other, and was 203 feet tall when first built. Egyptologists have guessed the Djoser pyramid completion dates were 2670–2650 BC. After it was built, skilled workers then spent a further 10 years connecting the pyramid with the Valley temple below, making its total construction time around 30 years. Because it was the first pyramid to be built, it took significantly longer to make than later pyramids of a similar size.

The Egyptian Pyramids of Giza Could Each Have Taken Between 15 and 27 Years to Build

The Great Pyramid of Giza was much larger in scale, at 455 feet tall. Accounts for its completion time vary from 20 to 27 years. The Great Pyramid stands as the tallest of three, alongside the Pyramid of Khafre, and the Pyramid of Menkaure. Together the group are known as the Giza Pyramid Complex and all were built as part of a frenzied, 60-year period of construction in ancient Egypt between roughly 2550 to 2490 BC, led by a series of powerful Egyptian Pharaohs. The Pyramid of Menkaure is the smallest of the three, and Egyptologists have guessed it took around 15 years to complete, so significantly less time than the Great Pyramid, because it is around half its size, at 200 feet. The Pyramid of Khafre is 448 feet high, sitting just below the Great Pyramid. It is guessed to have taken 20 years to complete, with ten years alone spent constructing its causeway.

How the Egyptian Pyramids Were Built So Quickly

Given that the Egyptian Pyramids have survived for over 4,000 years, the estimated time frames of 15 to 30 years that it took to build them seems relatively short. Egyptians had no access to the building techniques or modern machinery of today. Instead, it is thought by Egyptologists that unbelievably vast teams of skilled workers were involved in pyramid construction – some reports say 20,000 men, others 30,000, while others have guessed even 100,000 workers who used a series of complex sledges, rollers, levers and ramps.

Research still continues into how exactly such incredible structures were made in such short frames of time. Although we may never completely unravel the great mysteries of how long the Egyptian pyramids took to make, there is no doubt they are one of the most fascinating artefacts in the world, offering a window into one of the most complex and sophisticated human civilizations.

Who built the Pyramids of Giza?

Pharaoh Khufu was the first Egyptian king to build a pyramid in Giza, a project he began in circa 2550 B.C. His Great Pyramid is the largest in Giza and originally towered some 481 feet (147 meters) above the plateau—it’s a bit shorter now with its smooth casing stones long gone. Its estimated 2.3 million stone blocks each weigh an average of 2.5 to 15 tons.

Khufu’s son, Khafre, built the second pyramid at Giza, circa 2520 B.C. His necropolis, or burial ground, stands out on the landscape because it also includes the Sphinx, a mysterious limestone monument with the body of a lion and the head of a pharaoh.

The Sphinx, which before the 1800s spent thousands of years buried in the sand with only its head visible, may stand sentinel for the pharaoh’s tomb complex, although there’s no definitive proof that he built it.

The third of the Giza Pyramids is considerably smaller than the first two—less than half their height at about 218 feet. Built by Khafre’s son Menkaure circa 2490 B.C. the pyramid’s elaborate complex includes two separate temples connected by a long causeway, and three individual queens’ pyramids. Menkaure’s chambers include niche decorations unique to Giza and a vaulted ceiling in his burial chamber itself. The pharaoh’s elaborate sarcophagus was lost at sea near Gibraltar in 1838.

What were the pyramids made of?

The stones used in the building of the pyramids were not little bricks. The bricks in the pyramid vary in size. However, the largest can be found in the King’s chamber. These particular stones differ from the regular limestone blocks and were instead made of granite.

The precise method of raising the pyramids is not known. Pulleys were not invented until Roman times. However, the Greek historian Herodotus tells of levers being used to raise the blocks from one level to the next. It has also been suggested that workers operating in teams used a ramp to haul the blocks into position.  As the pyramid grew in size so the ramp would have been raised to enable the workers to reach the next level. The main problem with this is that the ramp would eventually have been huge as the pyramid itself and would have reached an immense distance into the desert.

How Did Egyptians Build the Pyramids?

The ancient engineering feats at Giza were so impressive that even today scientists and engineers can’t be sure exactly how the pyramids were built. Yet they have learned much about the people who built them and the political power necessary to make it happen.

The builders were skilled Egyptian workers who lived in a nearby temporary city sprawling over some 17 acres. The remains of bakeries and piles of animal bones show that they were very well fed for their labor. Archaeological digs on the fascinating site have revealed a highly organized community, rich with resources, that must have been backed by strong central authority.

What confuses archaeologists is how ancient Egyptians managed to haul these stones up onto the pyramid’s structure – with the biggest stones weighing between 25 and 80 tonnes.

Now scientists believe that these millennia-old builders used specialised ramps with wooden posts in, allowing teams of men to haul rocks upwards using a pulley-style system.

With 2.3million blocks making up the Great Pyramid, simply dragging rocks upwards from above required huge amounts of effort.

But scientists investigating inscriptions at the ancient Hatnab quarry accidentally unearthed a ramp with a 20% incline.

It was previously believed to be impossible for Egyptians to have pulled heavy blocks up ramps at more than a 10% incline – but this ramp was double the steepness.

The ramp had a surprising feature, however: post holes set alongside the steps on the side. According to Roland Enmarch, from the University of Liverpool, these holes would’ve been filled with thick wooden posts.

Teams of builders would then have wrapped ropes around the posts to create pulleys that allowed blocks to be pulled upwards from below.

This, when combined with a team of men pulling upwards, made it possible to have a steeper and more compact ramp.

The arrangement allows people to be spaced up and down the ramp, and all the force to be exerted in the same direction. Yannis Gourdon, of the French Institute for Oriental Archaeology, said the stones lifted from the quarry would’ve been a similar size to those used in the Great Pyramid.

Part of the problem for scientists, however, is that the ramps used to build the Great Pyramid were removed after construction. That means it’s impossible to know whether the exact same system was used at Giza. But Dr Enmarch described it as a “plausible inference”. He added: “This shows that at the time the Great Pyramid was being built, this technology was also being used.”

What are we still discovering about the pyramids?

The pyramids of Giza still hold plenty of secrets. And while scientists continue to make new discoveries, many of them also raise new questions.

The ScanPyramids project, an international team under the authority of Egypt’s Ministry of Antiquities, has been using modern technology to delve inside the pyramids since 2015 without setting foot inside. Advances in high-energy particle physics have allowed them to use cosmic rays to uncover various empty spaces that had been hidden for 4,500 years—including one void that rivals the size of the pyramid’s Grand Gallery and another passage, dubbed the North Face Corridor,  to the Pyramid of Khufu.

It’s unclear if anything is inside these spaces, but most experts believe they have no ritual significance. Instead, they were likely used during construction, a carefully engineered system to distribute the weight and stress of these iconic structures that have definitely stood the test of time.