The Nile River has two major tributaries: the Blue Nile and the White Nile. The Blue Nile (rich in alluvial silt) from Lake Tana in the highlands of Ethiopia, provides 80% of the Nile's water and snakes its way through eastern Sudan to Khartoum.
The slower flowing White Nile is born in the dark heart of Africa, the rift Valley lakes of Uganda, Rwanda and Burundi. It then transects southern Sudan and eventually meets the Blue Nile at the confluence near to Khartoum. It is here that the Nile is born and it is in Sudan where it diverts from its usual northerly course and flows for some time to the east and some time to the west before entering Egypt and Lake Nasser at Whadi Halfa.
The famous cataracts of the Nile are counted from the north and the first is found in Egypt at Aswan at the foot of the famous Cataract Hotel. The second cataract can be found just south of Whadi Halfa and then there are four more before you reach Khartoum. Sudan has made great use of this source of energy and one now finds dams at various places along the Nile, supplying most of the country’s electricity and making the rapids of the cataracts less impressive.