Why are river valleys productive farming areas?

River Valleys are productive farming areas because they provide fertile land by flooding.

Explanation:

Agriculture developed in river valleys as rivers flooded their banks, making lands around them fertile and provided fresh water for irrigation. Civilizations developed around rivers because their waters provided places to hunt and fish. Rivers brought along with fertile land along with minerals in it for crops to grow. Rivers allowed the early civilizations to engage in agriculture by growing crops like wheat, barley, and vegetables.

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