Smithsonian National Museum of Natural History

Down the Nile Valley

Every summer, the Nile flooded, carrying rich silt from volcanic uplands onto ancient Egyptian fields. The floodwaters also washed out salts that irrigation and evaporation left in the soil. The river’s annual cycle of renewing fertility nurtured a civilization that lasted nearly 5,000 years. The Egyptians called their land Kemet, or black land. The desert frontiers were Deshret, or red land. Ironically, the modern Aswan Dam now keeps the water table high, and irrigation leads to soil salinity.