The world's earliest river valley civilizations developed in the following locations:
- Mesopotamia - Situated between the Tigris and Euphrates Rivers, located in modern-day Iraq.
- Egypt - Centered around the Nile River, primarily in modern-day Egypt.
Other early river valley civilizations include the Indus Valley Civilization (along the Indus River in present-day Pakistan) and the Yellow River Civilization (Huang He) in China.