This is a personal question that only you can answer. However, we can provide some information that can help guide your work.
River valley civilizations were the first civilizations that arose in history. They formed in the banks of rivers, as these provided fertile ground to grow crops. Therefore, it is likely that if you travelled to these valleys, you would find a society that mostly relies on agriculture. These societies included the Ancient Egyptians (Nile River), the Mesopotamians (Tigris and Euphrates Rivers), Ancient Chinese (Yellow River) and Ancient Indians (Indus River).
These societies were also organized in a very particular way. It is likely that you would find a society where most people are farmers. They would form a particular social group. Other groups would include traders, priests and the nobility. Most of these civilizations consisted of a series of villages, with one or several large urban populations.