1. Istanbul in Turkey, a city poised between east and west, and between the present and the past. It's a good place to think about where all this comes from - not the physical structures of this particular city, but the invisible web that holds all cities together and which we humans have been spinning since the time of the very first cities, some 6,000 years ago. Civilisation is the best word for it. One of the most profound innovations in our human story. Historians today have become a little embarrassed by the word civilisation. We prefer less exalted terms like culture, community or society.
2. But in telling the stories of some of the first civilisations of the ancient world, I'll be making the case for civilisation itself. More than 4,000 years ago, an unknown poet listed the attributes of a successful city. The place where civilisation was first forged and where the aspirations of a civilisation still find their most concrete expression. The details of the poem are so vivid they could have been written yesterday. The warehouses are well provisioned and the houses within the city are well built. Those who bathe before the holidays rejoice in the courtyards.
3. And foreigners flock to and fro like exotic birds. The old women are full of good advice. The old men are full of good counsel. The young women are full of dancing spirit. The young men are full of fighting spirit. And the little ones are full of the spirit of joy. The people are happy. Of course, not everyone can be happy. But I believe the aspirations that this ancient poem expresses make as much sense to us now as they did 4,000 years ago. It's like that when you look down into the well of history. It gets dark so quickly, but sometimes, you catch a glimpse of something at the bottom, alive and moving and you suddenly realise it's your own reflection looking back at you.
4. That's the story I want to tell you now. It's not the story of Ancient Worlds long passed. It's the story of us, then. When we talk about the ancient world we tend to think of rare and exotic artefacts or the monumental remains of epic architecture. But these are just the empty shells that got left behind when the tide of history turned. The living creatures, the civilisations that once inhabited these shells were rarely, if ever, static or stately. They were dynamic, chaotic, and always threatening to spin out of control, because civilisation is based on an improbable idea that strangers can live together.
5. It's an idea we're still coming to terms with today, but one of the best ways to understand the challenges is to look at how our ancestors tackled them the first time around. In Baghdad, people know all too well just how precious civilisation is and how vulnerable. The Ancient Greeks believed that the cornerstone for all successful societies was eunomia, good order. Lost that and you're in danger of losing everything. Today, slowly and painfully, Iraqis are struggling to put back together the good order that dictatorship, regime change and civil war tore apart.
6. They live with hope that things will be better one day. It's a tall order but not an impossible one. In this part of the world it's a story that's been played out again and again from the time of the very first cities which appeared in this region some 6,000 years ago. We're in southern Iraq, just north of Basra, and I'm on my way to the place where this experiment in a new way of being human was first tried. The Ancient Greeks called this region Mesopotamia, "the land between two rivers", the Tigris and the Euphrates. But this is also the land between two seas - the Upper Sea and the Lower Sea, known to us as the Mediterranean and the Persian Gulf.
7. It's also the land between mountain and desert, lagoon and salt-marsh, and all of these geographical features have to borne in mind when considering the birthplace of the first civilisations. Geography versus history. It's impossible to know which takes precedence. But there's no getting away from the brutal facts of nature. Rivers that flood or dry up, rainfall that's intermittent, mountains that are impassable, deserts that are hostile. Applying this kind of analysis to Mesopotamia, where summers are hot, the winters are cold, and rainfall is low, I'd sum it up like this - difficult but not impossible.
8. No Garden of Eden, but no howling wilderness, either. People had occupied this marginal land for 1,000 years before the cities came. They arrived as pastoralists with their herds, they stayed on as farmers, clinging close to the river banks in scattered communities of 1,000 or 2,000 people at most. But then, just under 6,000 years ago, a remarkable thing happened. People left the security of their family compounds and tribal villages. They came together with other strangers to create something far more complex - a city, a society, a civilisation. The first place we know of where this radical experiment was tried is here - the ancient city of Uruk.
9. So, here it is. Uruk - the mother of all cities. Nowadays, as you can imagine, it's quite difficult to get to. But I'm glad I did. Athens, Rome, Constantinople, London, Paris, New York. Trace the family trees of all these great cities and they'd all lead back here to this dry and dusty corner of southern Iraq. Nowadays there's not much to see. But 5,000 years ago, this was home to 40,000 or perhaps 50,000 people. A population density unprecedented in human history. In the mythology of Mesopotamia, Uruk was built by Gilgamesh, two thirds god, one third human.
10. The great epic poem The Legend of Gilgamesh contains a proud description of his city. Go up, pace the walls of Uruk Study the foundation terrace and examine the brickwork Is not the masonry made of kiln-fired brick? And did not the Seven Sages lay its foundations? Three and a half square miles is the measure of Uruk! In fact, if anything, The Legend of Gilgamesh understates things. The walls of Uruk were nearly 10km in length, enclosing an area of six square kilometres. Just to give you a point of comparison, classical Athens, at its height, was no more than five square kilometres. And even Imperial Rome was little more than ten.
11. So, by the measures of the Ancient World, these first cities were neither small nor insignificant. From the very start, they were big players. Starting just under 6,000 years ago, the archaeological record of Uruk reveals a period of intensive building and rebuilding, which went on for four or five centuries. In that period, a dozen or more large public buildings were built. Temples, palaces, assembly halls. We don't know for sure what they were, but they were all of different shapes and sizes. And they used novel building techniques, like these cone mosaics, which once lined the walls here. You get the feeling that, behind all this restless building and rebuilding, the people of Uruk were searching for ways to express through architecture the new social structures that had come to be, in their new city, the shape of things to come.
12. But what kind of a society was being built at Uruk, and why had it come about? The answer can be found in the need to satisfy the most basic of all human needs. Hunger. Civilisation might have had its head in the clouds, but it marches on its stomach. This is the Euphrates, one of history's great rivers. 1,700 miles from source to delta. There's a lot of debate about where the name comes from, but some say it's derived from the Akkadian word frat which means fruitful. And it's certainly that - provided its waters can be got to the farmer's fields.
13. Agriculture - growing crops rather than raising livestock - pre-dates the first cities by thousands of years. But at some point, and quite suddenly, agricultural activity in Mesopotamia became more intensive and on a larger scale than had ever been seen before. This may have been in response to an environmental crisis - a prolonged period of drought or the sudden change in the course of the river, following a cataclysmic flood. For the first time since people had started living in this marginal land, their survival would have depended on finding ways to manage the waters, forcing them to think beyond the narrow concerns of their clans, and finding common cause with other clans.
14. Building dams and digging canals, to bring the water to the crops, on which all their lives now depended. The social consequences of this cooperation were profound. Those farmers weren't just digging ditches and selling barley, they were planting the seed from which the tree of civilisation would grow. But what turns the farmer in his field into a citizen of the city? To answer that question, I travelled 600 miles north from Uruk over the border into present-day Syria, to another ancient city, Tell Brak. The Syrians call this area Al-Jazeera, the Island, because it's situated between the Euphrates to the south and the Tigris to the north.
15. And the waters of both create an island of fertility in a sea of desert and mountain. And that is Tell Brak. It looks like a hill, but that impressive hump is actually man-made. The result of thousands and thousands of years of occupation, which has raised the level of the site 50 metres above the surrounding plain. Tell Brak stands as an impressive monument to the compulsive city-building activities of our ancestors. Excavations have been going on here since the 1930s, when the British archaeologist Max Mallowan, accompanied by his new bride, the crime writer Agatha Christie, first started working on Tell Brak.