(19 November - 5 December 1997) --- Featured in this view are Sudan's agricultural projects dependent on irrigation. Just southeast of the confluence of the Blue and White Nile rivers (and the city of Khartoum) is one of the largest irrigation projects in the world, known as the Gezira Scheme. The economy of Sudan is largely based on agriculture. The Gezira Scheme was begun by the British in 1925 and distributes water from the Blue Nile through canals and ditches to tenant farms lying between the Blue and White Nile rivers. Farmers cooperate with the Sudanese government and the Gezira Board. This network of canals and ditches is 2,700 miles (4,300 kilometers) long, and the irrigated area covers 2.5 million acres (1 million hectares). The main crop grown in this region is cotton. This picture is one of the 70mm Earth observations visuals used by the crew at its post flight presentation events..