The Nile is a major north-flowing river in northeastern Africa. It flows into the Mediterranean Sea. The longest river in Africa, it has historically been considered the longest river in the world, though this has been contested by research suggesting that the Amazon River is slightly longer. The Nile is amongst the smallest of the major world rivers by measure of cubic metres flowing annually. About 6,650 km long, its drainage basin covers eleven countries: Tanzania, Uganda, Rwanda, Burundi, the Democratic Republic of the Congo, Kenya, Ethiopia, Eritrea, South Sudan, Republic of the Sudan, and Egypt. In particular, the Nile is the primary water source of Egypt, Sudan and South Sudan. Additionally, the Nile is an important economic river, supporting agriculture and fishing. The Nile has two major tributaries – the White Nile, which begins at Jinja, Lake Victoria, and the Blue Nile. The White Nile is traditionally considered to be the headwaters stream.