History of Chad Africa's major language groupings south of the Sahara Desert (except Khoisan, which is not considered a valid genetic grouping anyway), i. e. the Afro-Asiatic, Nilo-Saharan and Niger–Congo phyla, originated in prehistoric times in a narrow band between Lake Chad and the Nile Valley. The origins of Chad's peoples, however, remain unclear. Several of the proven archaeological sites have been only partially studied, and other sites of great potential have yet to be mapped. At the end of the 1st millennium AD, the formation of states began across central Chad in the sahelian zone between the desert and the savanna. For
A3 highway (Nigeria) Gamboru-Ngala Local Government conveying commodities from the two countries are now left stranded on either sides of the bridge. On May 13, 2014, the House of Representatives "called on the Federal Government to rebuild the Gamboru Bridge linking the border town with other parts of Borno State." A3 highway (Nigeria) The A3 highway is a highway in Nigeria. It runs generally north from Port Harcourt through Aba, Umuahia, Okigwe, Enugu, Ngwo, Makurdi, Lafia, Jos, Bauchi and Potiskum thence east via Damaturu, Maiduguri to the border with Cameroon at Gambaru. The continuation through Cameroon connects to N'Djamena, the capital of Chad.