Luangwa River ago, there was no way out and the Luangwa Rift filled with a Rift Valley Lake called the Madumabisa Lake, which rivalled Lake Malawi in size. The water of the lake overflowed in a river to the south-west, towards what is now the Kalahari, where it combined with the Okavango, Upper Zambezi, Cuando and Kafue rivers, emptying into the Limpopo River and flowing to the Indian Ocean. Several geological events combined to produce the current river systems. Faulting produced another graben just to the south of the Luangwa Rift, and running east-west: the Zambezi Rift Valley and the Chicoa Trough.
Cuando River through a seasonal lake, Lake Liambesi (map, 7), it is called the Chobe (map, 8). The river then flows into the Zambezi just above the Kazungula Ferry (map, 9). In years when the Okavango experiences a good flood some of the water escapes east along the normally dry channel of the Magwekwana River (also known as Selinda Spillway) into the Linyanti Swamp, thus entering the Zambezi basin. The Selinda Spillway and the Boteti River are the only outlets of the Okavango basin. On the north side of the Chobe River are the Caprivi Swamps, on the edge of which is