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.
Zambezi term "Sena River" ("Rio de Sena"), a reference to the Swahili (and later Portuguese) upriver trade station at Sena. In 1752, the Zambezi delta, under the name "Rivers of Sena" ("Rios de Sena") formed a colonial administrative district of Portuguese Mozambique. But common usage of "Zambezi" led eventually to a royal decree in 1858 officially renaming the district "Zambézia". The Zambezi region was known to medieval geographers as the Empire of Monomotapa, and the course of the river, as well as the position of lakes Ngami and Nyasa, were given broadly accurately in early maps. These were probably constructed from