derives from the Zambezi River (Zambezi may mean "grand river"). History Prehistoric era Archaeological excavation work on the Zambezi Valley and Kalambo Falls shows a succession of human cultures. Ancient camp site tools near the Kalambo Falls have been radiocarbon dated to more than 36,000 years ago. The fossil skull remains of Broken Hill Man (also known as Kabwe Man), dated between 300,000 and 125,000 years BC, further shows that the area was inhabited by early humans. Broken Hill Man was discovered in Zambia in Kabwe District. Khoisan and Batwa Modern Zambia once was inhabited by the Khoisan and Batwa peoples until around AD 300, when migrating Bantu began to settle the areas. It is believed the Khoisan people originated in East Africa and spread southwards around 150,000 years ago. The Twa people were split into two groups: the Kafwe Twa lived around the Kafue Flats and the Lukanga Twa who lived around the Lukanga Swamp. Many examples of ancient rock art in Zambia, like the Mwela Rock Paintings, Mumbwa Caves, and Nachikufu Cave, are attributed to these early hunter-gatherers. The Khoisan and especially the Twa formed a patron-client relationship with farming Bantu peoples across central and southern Africa but were eventually either displaced by or absorbed into the Bantu groups. The Bantu (Abantu) The Bantu people or Abantu (meaning people) are an enormous and diverse ethnolinguistic group that constitutes the majority of people in much of eastern, southern and central Africa. Because of Zambia's location at the crossroads of Central Africa, Southern Africa, and the African Great Lakes, the history of the people that constitute modern Zambians is a history of these three regions. Many of the historical events in these three regions happened simultaneously, and thus Zambia's history, like many African nations', cannot be presented perfectly chronologically. The early history of the peoples of modern Zambia is deduced from oral records, archaeology, and written records, mostly from non-Africans. Bantu origins The Bantu people originally lived in West and Central Africa around what is today Cameroon and Nigeria. Around 4000 to 3000 years ago they began a millennia-long expansion into much of the continent. This event has been called the Bantu expansion; it was one of the largest human migrations in history. The Bantu are believed to have been the first to have brought iron working technology into large parts of Africa. The Bantu Expansion happened primarily through two