<P> A river civilization or river culture is an agricultural nation or civilization situated beside and drawing sustenance from a river . A river gives the inhabitants a reliable source of water for drinking and agriculture . Additional benefits include fishing, fertile soil due to annual flooding, and ease of transportation . The first great civilizations all grew up in river valleys . </P> <P> Civilization first began in 3500 BCE, which along the Tigris and Euphrates rivers in the Middle East; the name given to that civilization, Mesopotamia, means "land between the rivers". The Nile valley in Egypt had been home to agricultural settlements as early as 5500 BCE, but the growth of Egypt as a civilization began around 3100 BCE . A third civilization grew up along the Indus River around 2600 BCE, in parts of what are now India and Pakistan . The fourth great river civilization emerged around 1700 BCE along the Yellow River in China, also known as the Huang - He River Civilization . </P>

Why did river valleys became centers of civilizations
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