The second in length and largest in volume of the African rivers, rises NE. of the Muchinga Mountains in Rhodesia, flows SW. through Lake Bangueola, then N. to the equator; curving in a great semicircle it continues SW., passes in a series of rapids through the coast range, and enters the S. Atlantic by an estuary 6 m. broad. It brings down more water than the other African rivers put together. The largest affluents are the Kassai on the left, and the Mobangi on the right bank; 110 m. are navigable to ocean steamers, then the cataracts intervene, and 250 m. of railway promote transit; the upper river is 2 to 4 m. broad, and navigable for small craft up to Stanley Falls, 1068 m. The name most associated with its exploration is H. M. Stanley; during its course of 3000 m. it bears several names.