An erosional feature, dissected by seaward-flowing rivers, the nature of the escarpment varies according to the type of rock which forms it. Turning westwards the Great Escarpment is known successively as the Stormberg, Bamboes, Suurberg, Sneeuberg, Nieuwveld, and Komsberg, where gentle slopes affording access to the interior alternate with a more wall-like appearance. The south-eastern coastal belt, a very broken region descending to the coast in a series of steps, into which the rivers have cut deep valleys. The Cape ranges, consisting of the remnants of mountains folded during the Carboniferous era, and flanking the plateau on the south and south-west. Otherwise the Cape ranges are comparatively simple in structure, consisting of parallel anticlinal ridges and synclinal valleys.
Narrow lowlands separate the mountains from the coast.
Between the ridges and partially enclosed by them, e.g. the Little Karoo, is a series of steps rising to the foot of the Great Escarpment. The western coastal belt is also characterized by a series of steps, but the slope from the foot of the Great Escarpment to the coast is more gentle and more uniform than in the south-eastern zone. The greater part of the plateau is drained by the Orange river system. Rising in the Drakensberg within a short distance of the escarpment, as do its two main perennial tributaries, the Vaal and the Caledon, the Orange flows westwards for 1,900km before entering the Atlantic Ocean. However, the western part of its basin is so dry that it is not unknown for the Orange to fail to reach its mouth during the dry season.