Nile River

The Nile is a major north-flowing river in northeastern Africa, generally regarded as the longest river on Earth. It is 6,853 km long and discharges on average 2,830 m3/s of water. The Nile is an "international" river as its water resources are shared by eleven countries. In particular, the Nile is the primary water source of Egypt and Sudan.

Etymology
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 headwaters derive from Arabic names formerly applied only to the Sudanese stretches which meet at Khartoum.

Description
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 fertile soil. The White Nile is longer and rises in the Great Lakes region of central Africa, with the most distant source still undetermined. It then flows north. The Blue Nile begins at Lake Tana and flows into Sudan from the southeast. The two rivers meet near the Sudanese capital of Khartoum.

 The northern section of the river flows northwards almost entirely through the Sudanese desert to Egypt then ends in a large delta that 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.

Nile River's Role in Civiilization
The Nile River provided a crucial role in the development of Egyptian civilization. Silt deposits from the Nile made the surrounding land fertile because the river overflowed its banks annually. The Ancient Egyptians cultivated and traded wheat, flax, papyrus and other crops around the Nile. This trading system secured Egypt's diplomatic relationships with other countries, and contributed to economic stability. Far-reaching trade has been carried on along the Nile since ancient times.

Water buffalo were introduced from Asia, and Assyrians introduced camels in the 7th century BCE. These animals were killed for meat, and were domesticated and used for plowing—or in the camels' case, carriage. Water was vital to both people and livestock. The Nile was also a convenient and efficient means of transportation for people and goods. The Nile was an important part of ancient Egyptian spiritual life. Hapy was the god of the annual floods, and both he and the Pharaoh were thought to control the flooding. The Nile was considered to be a causeway from life to death and the afterlife. The east was thought of as a place of birth and growth, and the west was considered the place of death, as the god Ra, the Sun, underwent birth, death, and resurrection each day as he crossed the sky. Thus, all tombs were west of the Nile, because the Egyptians believed that in order to enter the afterlife, they had to be buried on the side that symbolized death.

As the Nile was such an important factor in Egyptian life, the ancient calendar was even based on the 3 cycles of the Nile. These seasons, each consisting of four months of thirty days each, were called Akhet, Peret, and Shemu. Akhet, which means inundation, was the time of the year when the Nile flooded, leaving several layers of fertile soil behind, aiding in agricultural growth. Peret was the growing season, and Shemu, the last season, was the harvest season when there were no rains.