Flaccus expedition: During Augustus times Lake Chad was a huge lake and two Roman expeditions were carried out in order to reach it: Septimius Flaccus and Julius Maternus reached the "lake of hippopotamus" (as Lake Chad was called by Ptolemy). They moved from coastal Tripolitania and passed near the Tibesti mountains. Both did their expeditions through the Garamantes' territories, and were able to leave a small garrison on the "lake of hippopotamus and rhinoceros" after 3 months of travel in desert lands.