Geography of the 4 ancient civilizations:
The geography of the 4 ancient civilization are similar because the 4 places where these civilizations started were along the sources of fresh water. Mesopotamia, along the Tigris and Euphrates rivers in modern Iraq, in India along the Indus River, in China along the Yangtze and Yellow Rivers, and in Egypt along the Nile.
These large source of water beside them not only were the ready source of water but also provided them food and made soil rich for cultivation to produce food. This somewhat easy availability of food sources gives ancient humans to fetch more time for other development.