Nile River

The Nile River flows over 6,600 kilometers (4,100 miles) until emptying into the Mediterranean Sea. For thousands of years, the river has provided a source of irrigation to transform the dry area around it into lush agricultural land. Today, the river continues to serve as a source of irrigation, as well as an important transportation and trade route.

The Nile has two major tributaries: the White Nile and the Blue Nile. The White Nile is traditionally considered to be the headwaters stream. However, the Blue Nile is the source of most of the water of the Nile downstream, containing 80% of the water and silt. The White Nile is longer and rises in the Great Lakes region. It begins at Lake Victoria and flows through Uganda and South Sudan. The Blue Nile begins at Lake Tana in Ethiopia and flows into Sudan from the southeast. The two rivers meet at the Sudanese capital of Khartoum.

Modern exploration of the Nile basin began with the conquest of the northern and central Sudan by the Ottoman viceroy of Egypt, Muhammad Ali, and his sons from 1821 onward. As a result of this, the Blue Nile was known as far as its exit from the Ethiopian foothills and the White Nile as far as the mouth of the Sobat River. Three expeditions under a Turkish officer, Selim Bimbashi, were made between 1839 and 1842, and two got to the point about 30 kilometers (20 miles) beyond the present port of Juba, where the country rises and rapids make navigation very difficult.

Lake Victoria was first sighted by Europeans in 1858 when British explorer John Hanning Speke reached its southern shore while traveling with Richard Francis Burton to explore central Africa and locate the great lakes. Believing he had found the source of the Nile on seeing this "vast expanse of open water" for the first time, Speke named the lake after Queen Victoria. Burton, recovering from illness and resting further south on the shores of Lake Tanganyika, was outraged that Speke claimed to have proven his discovery to be the true source of the Nile when Burton regarded this as still unsettled. A quarrel ensued which sparked intense debate within the scientific community and interest by other explorers keen to either confirm or refute Speke's discovery. British explorer and missionary David Livingstone pushed too far west and entered the Congo River system instead. It was ultimately Welsh-American explorer Henry Morton Stanley who confirmed Speke's discovery, circumnavigating Lake Victoria and reporting the great outflow at Ripon Falls on the lake's northern shore.