Geography of Sudan

Sudan is located in Northeast Africa. It is bordered by Egypt to the north, the Red Sea to the northeast, Eritrea and Ethiopia to the east, South Sudan to the south, the Central African Republic to the southwest, Chad to the west and Libya to the northwest. Covering 1,857,392 km² (717,143 sq mi), it is the third largest country in Africa, after Algeria and the Democratic Republic of the Congo. It was the largest country on the continent until South Sudan split off from it in 2011.

Northern Sudan –lying between the Egyptian border and Sennar– has two distinct parts, the desert and the Nile Valley. To the east of the Nile is the Nubian Desert and to the west, the Libyan Desert. Both are stony, with sandy dunes drifting over the landscape. There is virtually no rainfall in these deserts. Water in the Libyan desert is limited to a few small watering holes, such as Bir an Natrun, where the water table reaches the surface to form wells that provide water for nomads, caravans, and administrative patrols, although insufficient to support an oasis and inadequate to provide for a settled population. The Nubian Desert has no oases. Flowing through the desert is the Nile Valley, whose alluvial strip of habitable land is no more than two kilometers wide and whose productivity depends on the annual flood.

Sudan's western front encompasses the regions known as Darfur and Kurdufan that comprise 850,000 square kilometers. Traditionally, this has been regarded as a single regional unit despite the physical differences. The dominant feature throughout this immense area is the absence of perennial streams; thus, people and animals must remain within reach of permanent wells. Consequently, the population is sparse and unevenly distributed. Western Darfur is an undulating plain dominated by the volcanic massif of Jabal Marrah towering 900 meters above the Sudanic plain; the drainage from Jabal Marrah onto the plain can support a settled population and a variety of wildlife (see East Saharan montane xeric woodlands). Western Darfur stands in contrast to northern and eastern Darfur, which are semi-deserts with little water either from the intermittent streams known as wadis or from wells that normally go dry during the winter months. Northwest of Darfur and continuing into Chad lies the unusual region called the jizzu, where sporadic winter rains generated from the Mediterranean frequently provide excellent grazing into January or even February. The southern region of western Sudan is known as the qoz, a land of sand dunes that in the rainy season is characterized by a rolling mantle of grass and has more reliable sources of water with its bore holes and hafri (sing., hafr) than the north does. The highest peak in Sudan – Deriba caldera, of the Marrah Mountains – is in this region. A unique feature of western Sudan is the Nuba mountain range of southeast Kurdufan in the center of the country, a conglomerate of isolated dome-shaped, sugarloaf hills that ascend steeply and abruptly from the great Sudanic plain. Many hills are isolated and extend only a few square kilometers, but there are several large hill masses with internal valleys that cut through the mountains high above the plain.

Sudan's third distinct region is the central clay plains that stretch eastward from the Nuba Mountains to the Ethiopian border, broken only by the Ingessana Hills, and from Khartoum in the north to the far reaches of southern Sudan. Between the Dindar and the Rahad rivers, a low ridge slopes down from the Ethiopian highlands contrasting the neighboring plains as do the occasional hills. The central clay plains provide the backbone of Sudan's economy because of the large amounts of settlements which are there due to the available water. In the heartland of the central clay plains lies the jazirah, (literally in Arabic "peninsula") the land between the Blue Nile and the White Nile where the great Gezira Scheme was developed. This project grows cotton for export and has historically produced more than half of Sudan's revenue and export earnings.

Northeast of the central clay plains lies eastern Sudan, which is divided between desert and semi-desert and includes the Butana, the Qash Delta, the Red Sea Hills, and the coastal plain. The Butana is an undulating land between Khartoum and Kassala that provides good grazing for cattle, sheep, and goats. East of the Butana is a geological formation known as the Qash Delta. Originally a depression, it has been filled with sand and silt brought down by the flash floods of the Qash River, creating a delta above the surrounding plain. Extending 100 kilometers north of Kassala, the whole area watered by the Qash is a rich grassland with bountiful cultivation long after the river has spent its waters on the surface of its delta. Trees and bushes provide grazing for the camels from the north, and the rich moist soil provides an abundance of food crops and cotton.

Northward beyond the Qash lie the Red Sea Hills. Dry, bleak, and cooler than the surrounding land, particularly in the heat of the Sudanese summer, they stretch northward into Egypt, a jumbled mass of hills where life is hard and unpredictable for the Beja inhabitants. Below the hills sprawls the coastal plain of the Red Sea, varying in width from about fifty-six kilometers in the south near Tawkar to about twenty-four kilometers near the Egyptian border. The coastal plain is dry and barren. It consists of rocks, and the seaward side is thick with coral reefs.

Sudan has islands located in the Nile and other rivers, in lakes and reservoirs and in the Red Sea.

Tuti Island, Aba Island, Badien Island, Sai Island.