3
All over the earth we find rivers, large and small, whose tributaries reach to the far corners of the world. Whether meandering
or carving powerfully through the landscape, rivers determine our way of being in the world. They present pathways for
explorers and obstacles for armies. We rely on them as sources of drinking water, for fishing and for irrigating our fields.
By gravity, rivers empty into oceans, lakes, swamps or other rivers. We harness the power of flowing water to drive machines
that generate power. Understanding rivers allows us to understand people and the ways we have lived alongside them for
centuries. According to the Greek historian Herodotus, Egypt was “the gift of the Nile”—the river made Egyptian civilization
possible. The same could be said of Mesopotamia’s Tigris and Euphrates, of China’s Yellow River, of the rivers of many cultures,
past and present. Let’s take a journey along seas, lakes and rivers.
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