Lake Chad At its largest extent the river Mayo Kébbi represented the outlet of the paleolake Mega-Chad, connecting it to the Niger River and the Atlantic. The presence of African manatees in the inflows of Lake Chad is an evidence of that history. Romans reached the lake in the first century of their empire. Indeed, during the time of Augustus lake Chad was still a huge lake and two Roman expeditions were done in order to reach it: Septimius Flaccus and Julius Maternus reached the "lake of hippopotamus" (as the lake was called by Claudius Ptolemaeus). They moved from coastal Tripolitania and
Geography of Chad extends west into Nigeria and Niger. The larger, northern portion of the basin is bounded within Chad by the Tibesti Mountains in the northwest, the Ennedi Plateau in the northeast, the Ouaddaï Highlands in the east along the border with Sudan, the Guéra Massif in central Chad, and the Mandara Mountains along Chad's southwestern border with Cameroon. The smaller, southern part of the basin falls almost exclusively in Chad. It is delimited in the north by the Guéra Massif, in the south by highlands 250 kilometers south of the border with Central African Republic, and in the southwest by the