What was in the early cities in the old stone age?

The oldest known civilization is Sumer, and it is an example of a stone age civilization. The Sumerians built cities of stone, and even devised underground sewage systems using pipes of baked brick. They developped the earliest writing that we know about, and used it to record many forms of literature. While this civilization was flourishing in the fertile crescent, neighboring peoples in drier areas were nomads, either hunting and gathering, or living from the flocks and herds they kept. There have been settlements growing into cities, as clime and other factors allow, as long as there have been segments of the population living by other methods.