Ken Follett

and then tunnels radiating out from the shaft at the bottom.

And this was the only industry in the Stone Age.

And these flints were terrifically valuable.

They tell us a bit about the Stone Age.

Because look, the guys who dug the shafts and mined the flints, you can't eat the flints.

So they must have traded them.

for what they needed to live, food and clothing and leather for their shoes and so on.

That tells us that there was some kind of organized trade in the Stone Age, something that we might not necessarily have known otherwise.

And I wonder whether it was also a kind of currency.

I mean, there was no money in the Stone Age, but I suppose if you wanted to, as it were, put a bit aside for a rainy day, if you had a box full of costly flints, you could stash it.

And then in hard times, you could get one out and trade it for a piece of beef or something.

So it was key in that respect.

The other thing that we can find, talking about a piece of beef, we can find out a bit about what they ate.

Because as I'm sure you know, and when archaeologists dig down in what's called a midden, which is actually full of Stone Age poo,

It's not actually stinky.

It's just like earth.

It doesn't have any bacteria left because it's been there for 4,500 years.

But they can examine it.

And obviously, it shows them what food was eaten.

So we know, for example, that they were carnivores.