 thumb|330 px|map of the river's course the atbarah river (; transliterated: nahr 'atbarah) in northeast africa rises in northwest ethiopia, approximately 50&nbsp;km north of lake tana and 30&nbsp;km west of gondar. it flows about 805&nbsp;km (500&nbsp;mi) to the nile in north-central sudan, joining it at the city of atbarah (). its tributary, the tekezÃ© river, is perhaps the true upper course of the atbarah, as the tekezÃ© follows the longer course prior to the confluence of the two rivers (at 14Â° 10' n, 36Â° e) in northeastern sudan. the atbarah is the last tributary of the nile before it reaches the mediterranean. for much of the year, it is little more than a stream. however during the rainy season (generally june to october), the atbarah rises some 18&nbsp;ft (5 m) above its normal level. at this time it forms a formidable barrier between the northern and central districts of the amhara region of ethiopia. besides the tekezÃ©, important tributaries of the atbarah include the shinfa river which rises west of lake tana, and the greater angereb which has its source north of the city of gondar. the earliest surviving mention of the atbarah is by strabo (16.4.8), who called the river astaboras ().claude rilly, le mÃ©roÃ¯tique et sa famille linguistique, peeters, louvain 2010, p. 179 other ancient authors mentioning the name include agatharchides, who called it astabaras (), and ptolemy (geography 4.7). richard pankhurst and others have argued that the name should be understood as "river of the boras people", where asta can be related to proto-nubian asti "water", while -boras can be linked to a number of roman allusions to a tribe named the bora, who lived near meroe,richard pankhurst, the ethiopian borderlands (lawrenceville: red sea press, 1997), p. 27 and another tribe named the megabares ( in eratosthenes and strabo,  in pliny the elder). [
Atbarah_River International_rivers_of_Africa Nile_basin Rivers_of_Ethiopia Rivers_of_Sudan Tributaries_of_the_Nile