How Were The Pyramids Actually Built? Egyptologist Answers.

As an Egyptologist, my phone rings off the hook whenever

the news story breaks: new satellite imagery, new scans,

new theories-a new discovery has solved the mystery

of the pyramid-but it's usually a big nothing burger.

We actually have a pretty good understanding

of how Khufu's pyramid was built,

and that understanding comes from multiple discoveries,

five of which we're going to dive into right now.

Discovery number one: the Giza Quarry.

There is a lot of stone in the Great Pyramid

and the Giza Plateau.

Where on earth do these stones come from?

Most of the stone that was used to build

the Great Pyramid at Giza was the bedrock of Giza itself.

We have, in fact, an area that was a quarry,

a very large horseshoe-shaped quarry south of the pyramid

that was used to pull up the blocks

that were then used in the pyramid.

Let me show you how you could get a block of stone

out of a quarry like this.

It sounds really inexact,

but it can actually be done fairly well.

So, looking from the top first,

you're going to take a hard stone,

a stone like granite or diorite,

and you're going to drop it onto the ground in a track,

so, in a line.

It takes a lot of dropping to chip this away,

but you're doing it.

You're going to do this in a bunch of lines.

Then you get a lattice of trenches,

narrow trenches made by dropping a hard stone

onto the soft stone of the limestone repeatedly.

And you go down for a couple of meters like this.

Now, looking from the side, you have these narrow trenches.

How are you going to knock this block off that you want

to have knocked off?

You've only defined this on the sides from the top.

Well, here you go again with your stone tools.

It's harder to do this because you don't have gravity,

but you chip away the sides.

And then you put a log in each of these.

When you wet the log, the wood is going to expand.

And as the wood expands, it cracks right here.

Now you have a beautifully shaped block

that you can pick up and take to your ramp.

Discovery two: the ramps.

This is the big question: How on earth did you raise

so much heavy stone into this shape, this height,

before modern technology?

We've known that there must be ramps involved.

We do not have ramp remains at Giza itself.

This is one reason why this is fertile ground for theories

and imagining of what the ramps might have looked like.

But, in fact, we know a great deal about what ramps looked

like in ancient Egypt.

Probably the best remaining example of an actual ramp

that we have from Egypt comes from the site

of Karnak at Thebes.

Karnak is a huge temple.

It's considerably later than the pyramids at Giza,

but it does show us a lot

about Egyptian construction techniques.

And, particularly, it shows us the building of a mud brick

ramp that was used to construct a massive stone building.

One reason the ramp at Karnak is so cool is

because they left the site as a construction site.

It was never finished.

Very often, we don't have evidence of construction process

because they cleaned up.

At Karnak, that wasn't the case.

At Giza, the construction process was finished,

and, as such, they removed the remains of the ramp,

probably as part of smoothing down the pyramids

as they finished them.

So, the two basic ideas are either that a ramp

would've been straight and gone up the side of the pyramid,

or that a ramp used the pyramid itself as the basis

that supported it and spiraled up around the pyramid,

growing as the pyramid grew.

A straight ramp for a building as large

as the pyramid is improbable.

The ramp would've had to be extremely long

to maintain a shallow angle of incline

for dragging the blocks up once you got to the top.

You look at the entire plan of Giza

and think how much territory

would have to be covered by a ramp?

That means your starting place for dragging the blocks

up is very far away.

It's an enormous amount of material,

and it's less likely that there would be nothing left

for us to find.

So, both practically and in terms of the evidence

that we have from the site,

a spiraling ramp up the pyramid

is substantially more probable,

particularly for the higher levels of the pyramid.

So, it's one thing to build a ramp.

It's another thing to get the blocks up the ramp.

How do you actually do that?

To get a block of this size up the ramp,

you put it on a wooden sledge.

These are runners of wood.

They're flat.

These are not rollers.

We're not using wheels or rolling of any sort.

And you pull the sledge up.

The sledge is attached to ropes,

and you have a human labor force.

It doesn't seem that they're using animals

in this case, just people.

You can ease that process somewhat by lubricating

the ground underneath the sledge,

by pouring water in front of the sledge as it's going up.

And it would've taken many men

to pull a single block of stone.

It's backbreaking labor.

This would've been extremely dangerous and difficult.

But ramps didn't build the pyramids alone.

What is very clear is that an enormous number

of people were needed to haul the stones up those ramp.

And that takes us to our next discovery:

the work mans' village at Giza,

sometimes called the Lost City.

Archeologists since the 1980s have been working

at the Giza Plateau, trying to understand not only

the vast monuments that are symbols of kingship,

but also what the site might teach us about the process

of building the pyramids and, in particular,

about the people who were part of that.

The site of the workers' village at Giza

is not immediately adjacent to the pyramids.

It is rather closer to the cultivation,

down a bit from the main plateau.

While our estimates of the number of people

who it would've taken to build the Great Pyramid

are wildly variable,

usually somewhere in the range of 10 to 20,000 people,

it is clear that the workers' village could have supported

a really large percentage of this population.

The town that has been uncovered since the 1980s

is enormous, and it contains many different

types of evidence.

We have, for instance, the bakeries,

the place where they were baking the bread

that is the main food source

for the construction crews who are working on the pyramids.

We have long galleries that have been interpreted

as sleeping places, as barracks for seasonal workers.

We have houses for people who lived year round

at the pyramid construction site.

We have animal pens where the other main food source

for the population here lived.

Now, meat was not a regular part of the diet

of most Egyptians, but the level of animal keeping

that we're seeing here argues that the people

who were building the pyramids absolutely needed

a high-protein diet that may very well relate to the fact

that people here are doing an incredible amount of labor.

Another element we have at the workers' village

is we have these enormous silos for storing grain.

Bread is one thing you make with grain,

but another thing you make is beer.

Beer was a staple food in ancient Egypt,

and it is even given as part of payment to people.

Understanding how a workforce is paid in Egypt

is a little bit complicated

because money hadn't been invented yet.

So, people are being paid for their time,

but they're being paid in food, in bread and beer,

the staple foods, often being paid more than they themselves

would have consumed.

That's what allows you to keep a family

or, if you're paid way more,

to be a patron yourself and hire others.

And people were paid for their work at the pyramids.

We do have questions about the labor status,

whether or not those who built the pyramids were slaves.

It's a really normal question to ask.

And we don't really have good evidence

as to whether or not they made the choice

to work on the pyramids or whether they were owned.

There's a lot of room in between.

Discovery number four: the Diary of Merer.

In 2013, archeologists working at the site of Wadi el-Jarf,

on the coast of the Gulf of Suez,

discovered a cache of papyri

that dated back to the Fourth Dynasty.

The papyri at Wadi el-Jarf included the diary

of an official named Merer

and a day-by-day account of activities directly

relating to the construction of the pyramids.

This is the earliest known inscribed papyrus

that we have from ancient Egypt.

Papyrus is a material that is made by splitting the stocks

of papyrus plants that is kept in a long scroll.

The papyri that have been translated

so far are of particular importance for telling us

about the activities of the official Merer.

Merer was in charge of a workforce

that was quarrying stone for the outer parts of the pyramid.

In Merer's diary, he doesn't talk specifically

about the activities of quarrying,

but he does talk about the transport of the blocks,

and he gives us, particularly, the itineraries

of where his crew were at any given time.

So, at the top of every column here,

we get a number that's a date.

He is recording exactly what's happening on any given date,

keeping track, close track, of these large groups of men

who are responsible for transporting the blocks.

We know that it took two days to go

from the site called Tura,

which is on the East Bank of the Nile,

to the pyramid site at Giza, on the West Bank.

It's not that far, but transporting these really

large blocks of stone took two days round trip,

and the crew turned right back around to go back

to the quarry as soon as they had dropped off the blocks.

So, if we look at this papyrus,

one thing we can see is how frequently

the name of Khufu is present.

That is the king for whom the pyramid was being built.

It's usually because Merer is referring to places

where he is taking the stone,

and the places themselves are named

in a way that incorporates the name of Khufu.

So, it's calling Giza Khufuville, for instance.

Discovery five: the early pyramids.

Sometimes, we approach Giza as though it were a marvel

that came into being with no precedent,

as though it were the only site where pyramids are.

But, in fact, Giza was built at the end, not the beginning,

of a process of discovering how to build large buildings.

The first pyramid in Egypt,

which was built at the site of Saqqara,

was built well over a hundred years

before Khufu built his pyramid.

The step pyramid at Saqqara is built

in a very different way.

The blocks of stone, which were quarried at Saqqara,

are smaller than the blocks of the Great Pyramid.

The pyramid itself is not square at its base.

It's rectangular.

It shows today as though it's a big layer cake,

with the layers of diminishing size, because it's stepped.

But also, significantly, each layer of stones,

rather than being laid flat,

is laid so that it is at an incline.

It's tilted.

We can see here that they're figuring out

how to build in stone.

Nobody else had ever built a building

in stone in Egypt here.

They built and figured out how to build by doing it,

and they changed their minds and their techniques

as they were constructing.

The other reign that is really important

is the reign of King Sneferu, the father of Khufu.

Sneferu actually built three different pyramids.

The first pyramid was built much like

the pyramid of Djoser at Saqqara,

with leaning courses and a stepped structure.

The second pyramid of Sneferu appears

to have run into engineering difficulties,

and they changed the angle partway through,

probably because of structural weaknesses

that were encountered because of the weight of stones.

It's now called the bent pyramid because it's bent.

The sides are at a noticeably different angle

in the bottom half of the pyramid

and the top half of the pyramid.

Sneferu, when he builds the bent pyramid,

he's going for a true pyramid structure, but it fails.

It's the wrong size and shape

for what the ground can accommodate.

The last pyramid that Sneferu built,

which we call the red pyramid, is of a much shallower angle.

Perhaps, again, because they had learned through the process

of messing up with the bent pyramid that a steeper angle

meant too much weight on top.

By the time Khufu comes to build his pyramid

on a much more stable plateau, with stronger limestone,

he has all of the lessons that he was able to learn

from the successes and failures of his predecessors.

So, if you ask me how the Great Pyramid of Giza

was truly built, I would say it was built

after an enormous amount of trial and error.

And that trial and error over previous generations was trial

and error on a bunch of different fronts.

It was trial and error figuring out how to recruit

and organize and feed an enormous workforce;

development of writing and record keeping,

enabling that kind of organization.

It is the exploitation of sites far afield

from where the pyramids are built.

It is trial and error

on a construction and engineering front:

what kind of ramps will work?

It took generations to figure that out,

and trial and error on keeping and feeding

an entire workforce at the site

so that they're ready to perform their labor.

The Great Pyramid is an awe-inspiring, amazing monument.

To stand in its shadow is to be overwhelmed.

But, as generations of scholarship have taught us,

it is also a deeply human monument,

something that was built by people,

people who figured out how to organize themselves,

how to do the engineering,

how to construct this amazing thing.

We continue to learn more through new discoveries

about this monument and to refine our understanding

of the people who built it.

Thank you for watching.

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