Centers of intensive agriculture and irrigation in East Africa.

Another Pokot furrow, taken from Tororro stream in the Wei wei valley. This furrow contours across the valley sides for some 2.5 miles (4 kilometers), supplying water to numerous maize fields. The furrow is substantially built, especially in its upper course where large stone slabs reinforce the down-slope side of the furrow. Courtesy Matthew Davies, British Instiitute in Eastern Africa, Nairobi.