The Nile is the longest river in the world at 4,132 miles long and is the site and lifeblood of the ancient Egyptian civilization. The name of the Nile comes from the Greek word "neilos," which may be derived from the Semitic "nahal," or "river."
The Nile river basin, situated in the countries of Egypt, Sudan, Ethiopia, and Uganda, is formed from the convergence of three streams, the White Nile, the Blue Nile, and the Atbara. The White Nile originates from the headstreams of Lake Victoria and Lake Albert. The Blue Nile and the Atbara flow from the highlands of Ethiopia. Unusually, the Nile flows from south to north emptying into the Mediterranean Sea.
The ancient Egyptians called the river "Ar," or "black," after the sediments deposited during the annual flood season. The Nile as the source of water and fertile, nutrient-rich soil allowed several ancient civilizations to flourish. The ancient Egyptian civilization in particular constructed multiple temples and monuments by the river, and even to this day agriculture and urban development flourish along the Nile's banks. However, the modern-day Nile has been irrigated extensively and features multiple dams. The Aswan Dam in particular limits the extent of the flooding.