Flowing for 5584 km, the Nile is the longest river in the world. Its delta empties into the Mediterranean Sea. The beginning of the Nile River is south of the delta, which makes people from the Northern Hemisphere think it flows in the wrong direction.
Lake Victoria, Egypt's largest lake and the second largest freshwater body in the world, feeds the Nile. Lake Victoria is located in Tanzania and Uganda, and a small part of Kenya. From Lake Victoria going north, this longer segment of the Nile, from Malakâl to Khartoum is sometimes called the White Nile, as distinguished from the Blue Nile, which feeds into the river at Khartoum, from a southeasterly Ethiopian source at Lake Tana.
Early people required reliable or predictable water supplies for agricultural and then commercial settlements to develop. In ancient Egypt, the flooding of the Nile was predictable enough for the Egyptians to plan their yearly crops around it. It flooded annually sometime from June to September, as a result of monsoons in Ethiopia. The famine resulted when there was inadequate or surplus flooding. The ancient Egyptians learned partial control of the flood waters of the Nile by means of irrigation. They also wrote hymns to Hapy, the Nile flood god.
In addition to being a source of water for their crops, the Nile River was a source of fish and a major artery linking parts of Egypt as well as linking Egypt to its neighbours. From one ancient period to the next, the course of the Nile and the amount of silt deposited varied. This process continues.
From 'The Nile River and Nile Delta in Egypt' in N.S. Gill's Ancient/Classical History Glossary , <https://www.thoughtco.com/nile-river-nile-delta-in-egypt-111649>