river in southern Africa, rising in central Angola and flowing southeast, forming for nearly 140 miles (225 km) the boundary between Angola and Zambia. Near the end of its course the Kwando reaches the northern boundary of the Caprivi Strip, which juts out from Namibia, and thereafter the river spreads into the Linyanti Marshes, covering about 550 square miles (1,425 square km) and including Lake Liambezi. The marshes drain eastward toward the Zambezi, both rivers sharing the same floodplain. The confluence of the rivers is about 6 miles (10 km) below an exposure of basalt that the Zambezi clears at the Mambova Rapids and the Kwando (known in this region as the Chobe, or the Linyanti) clears at the Kasane Rapids. In May the Chobe's water level rises at the northern Caprivi boundary, reaching high flood level in June. The total length of the river is 457 miles (731 km), and its drainage basin covers 37,366 square miles (96,778 square km).