6,000 years before the present, the colossal city of Uruk, by far the largest in the world,

dominated the southern Mesopotamian plains of modern-day Iraq.

With a population of at least 50,000 people, Uruk wouldn't be surpassed in size or in numbers

for an astonishing 3,000 years to come, until well into the classical age.

The legendary homeland of Gilgamesh, a colossal mud-brick wall said to have been erected by the

great hero king himself, once enclosed the city's impressive 6-kilometer radius. Yet, impressive

as it was, Uruk didn't exist in a vacuum. The city was simply the latest, albeit most successful in a long line of similar experiments

in living, dating all the way back to the Stone Age.

More than 5,000 years before the founding of Uruk, other smaller, though no less impressive

settlements had began to coalesce and form in this region of the world.

The very first known examples of static, communal living in history.

In other words, though the exact definition varies, the first cities on earth.

The most well known of these settlements, perhaps due to its often cited links to the Biblical

walls of Jericho of the Old Testament, remains arguably the most impressive of all.

Jericho is a place of firsts. Here, 5,000 years before Uruk, can be found the first known settlement

in history to be surrounded by walls. Some of the earliest evidence of cooperation between

a group larger than a single clan or kinship, the first significant evidence of large-scale communal labour,

and when it was first discovered, the first tower, complete with walled steps in history.

What makes this especially striking is that besides a scattering of mysterious pictographic symbols,

writing wouldn't develop for thousands of years to come.

Even pottery didn't exist yet, though, nevertheless, these people still came together here all those millennia ago and achieved

something astonishing.

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