– The Early Cities
In the historical evolution of the first urban civilizations and their cities it is possible to discern three main phases. Each of these involved 'radical and indeed revolutionary innovations in the economic sphere in the methods whereby the most progressive societies secure a livelihood, each followed by such increases in population that, were reliable statistics available, each would be reflected by a conspicuous link in the population graph'. I
The first of these phases covers the whole of the Palaeolithic Age, from its origins, at least half a million years ago, until around 10000 BC, followed by the proto-Neolithic and Neolithic Ages. These in turn lead to the fourth phase, the Bronze Age, starting between 3500 and 3000 BC and lasting for some 2,000 years. During this last period the first urban civilizations were firmly established.