180miles
Cataracts can also be known as rapids and the link below gives the information about the Nile cataracts. any furious rush or downpour of water
the area is 200mi also it is part of Nubia
Since the first cataract is at Aswan, the area north of it is Egypt.
Cataracts, then, can be classified according to location (nuclear, cortical, or posterior subcapular cataracts).