>> The Nile has two major tributaries, the White Nile and Blue Nile

The Nile is a major north-flowing river in northeastern Africa, generally regarded as the longest river in the world. It is 6,853 km (4,258 miles) long. The Nile is an "international" river as its water resources are shared by eleven countries, namely, Tanzania, Uganda, Rwanda, Burundi, Congo-Kinshasa, Kenya, Ethiopia, Eritrea, South Sudan, Sudan and Egypt. In particular, the Nile is the primary water source of Egypt and Sudan.

The Nile has two major tributaries, the White Nile and Blue Nile. The White Nile is considered to be the headwaters and primary stream of the Nile itself. The Blue Nile, however, is the source of most of the water and silt. The White Nile is longer and rises in the Great Lakes region of central Africa, with the most distant source still undetermined but located in either Rwanda or Burundi. It flows north through Tanzania, Lake Victoria, Uganda and South Sudan. The Blue Nile (Amharic: ዓባይ?, ʿĀbay  ) begins at Lake Tana in Ethiopia and flows into Sudan from the southeast. The two rivers meet near the Sudanese capital of Khartoum.

The Nile's watershed

The northern section of the river flows north almost entirely through the Sudanese desert to Egypt, then ends in a large delta and empties into the Mediterranean Sea. Egyptian civilization and Sudanese kingdoms have depended on the river since ancient times. Most of the population and cities of Egypt lie along those parts of the Nile valley north of Aswan, and nearly all the cultural and historical sites of Ancient Egypt are found along riverbanks.

In the ancient Egyptian language, the Nile is called Ḥ'pī or Iteru, meaning "river", represented by the hieroglyphs shown on the left (literally itrw, and 'waters' determinative). In Coptic, the words piaro (Sahidic) or phiaro (Bohairic) meaning "the river" (lit. p(h).iar-o "the.canal-great") come from the same ancient name.

The Blue Nile Falls fed by Lake Tana near the city of Bahir Dar, Ethiopia.

The English name Nile and the Arabic names en-Nîl and an-Nîl both derive from the Latin Nilus and the Ancient Greek Νεῖλος. Beyond that, however, the etymology is disputed. One possible etymology derives it from a Semitic Nahal, meaning "river". The standard English names "White Nile" and "Blue Nile", to refer to the river's source, derive from Arabic names formerly applied only to the Sudanese stretches which meet at Khartoum.
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