Life went through some incredible changes when the first cities were built. Up until then, nearly every person had to work as a farmer or a hunter, moving from place to place in a constant struggle to survive.

All that changed about 7,000 years ago, when Sumer, the first civilization, began. For the first time in human history, people moved into the safety of a walled city. For the first time, they didn’t have to hunt or farm. They could become builders, astrologers, and teachers. They could develop things that, until then, no one had ever even dreamed of.