All the early civilizations occurred somewhere with a access of moving water, which is important in providing fresh water, silt, and other less essentials such as fish.
Deposits of silt was extremely important to early civilizations, as silt is comprised of an extremely nutrients rich soil, which would layer on top of the ground during seasons of flooding, which would then in turn give a good bed in which plants can grow on. Fresh Water could be found in rivers such as the Nile River, which saw the inclusion of drinkable (pottable) water, fresh water fish (which provides protein), as well as chances to bathe (which promotes health).
Water is essential in maintaining life, and without adequate, drinkable amounts, plants, animals, as well as humans cannot survive. What each of these rivers provide to their respective civilizations is the ability to survive with pottable water, and with their necessities met, humanity was able to continue advancing technologically, intellectually, and systematically.
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