Wadi Howar (Wadi Howa) is a

wadi Wadi ( ar, وَادِي, wādī), alternatively ''wād'' ( ar, وَاد), North African Arabic Oued, is the Arabic term traditionally referring to a valley. In some instances, it may refer to a wet (ephemeral) riverbed that contains water ...

Sudan Sudan ( or ; ar, السودان, as-Sūdān, officially the Republic of the Sudan ( ar, جمهورية السودان, link=no, Jumhūriyyat as-Sūdān), is a country in Northeast Africa. It shares borders with the Central African Republic t ...

and

Chad Chad (; ar, تشاد , ; french: Tchad, ), officially the Republic of Chad, '; ) is a landlocked country at the crossroads of North and Central Africa. It is bordered by Libya to the north, Sudan to the east, the Central African Republic ...

Geography

Originating in the

Ennedi Region Ennedi Region was a former region of Chad. It was created in 2008 from the Ennedi Est Department and Ennedi Ouest Department of the former Borkou-Ennedi-Tibesti Region. The capital of the Ennedi region was Fada. In 2012 it was split into two ...

''Wadi Howar'' runs through the Sudanese states of North Darfur and

Northern Northern may refer to the following: Geography * North, a point in direction * Northern Europe, the northern part or region of Europe * Northern Highland, a region of Wisconsin, United States * Northern Province, Sri Lanka * Northern Range, a r ...

to join the Nile north of the great bend opposite Old Dongola. Stretching over 1100 km in west–east direction across the southern fringes of the

Libyan Desert The Libyan Desert (not to be confused with the Libyan Sahara) is a geographical region filling the north-eastern Sahara Desert, from eastern Libya to the Western Desert of Egypt and far northwestern Sudan. On medieval maps, its use predates ...

, it ordinarily receives 25 mm of rainfall per year.

Holocene period

''Wadi Howar'' is the remnant of the ancient ''Yellow Nile'', a tributary of the

Nile The Nile, , Bohairic , lg, Kiira , Nobiin: Áman Dawū is a major north-flowing river in northeastern Africa. It flows into the Mediterranean Sea. The Nile is the longest river in Africa and has historically been considered the longest riv ...

during the Neolithic Subpluvial from about 9500 to 4500 years ago. At that time

Savanna A savanna or savannah is a mixed woodland- grassland (i.e. grassy woodland) ecosystem characterised by the trees being sufficiently widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground ...

fauna and cattle-herders occupied this region and the southern edge of the

Sahara , photo = Sahara real color.jpg , photo_caption = The Sahara taken by Apollo 17 astronauts, 1972 , map = , map_image = , location = , country = , country1 = , ...

was some 500 km further north than it is today. When the Sahara underwent

desertification Desertification is a type of land degradation in drylands in which biological productivity is lost due to natural processes or induced by human activities whereby fertile areas become increasingly arid. It is the spread of arid areas caused ...

between 6000 and 4000 years ago, the wadi first became a chain of freshwater lakes and marshes, as shown by

Ptolemy's world map The Ptolemy world map is a map of the world known to Greco-Roman societies in the 2nd century. It is based on the description contained in Ptolemy's book '' Geography'', written . Based on an inscription in several of the earliest surviving manu ...

, then it became extinct about 2000 years ago.

Archaeology

Abundant prehistoric sites certify ''Wadi Howar'' as a once ecologically favoured area of settlement and a communication route between the inner regions of Africa and the Nile Valley. The hitherto most thoroughly investigated archaeological site in the wadi is

Gala Abu Ahmed Gala Abu Ahmed is a fortress ruin in lower Wadi Howar, northern Sudan. The facility is located west of the Nile. The fort was discovered in 1984 by archaeologists from the University of Cologne. It dates to the Napatan phase (ca. 750-350 BC) of t ...

References

{{Authority control Howar Nile Rivers of Sudan Rivers of Chad International rivers of Africa Chad–Sudan border North Darfur

Geography

Holocene period

Archaeology

See also

References