Lake Chad is an inland lake located in southeastern Niger in the Diffa region, with four countries sharing its shores: Chad, Cameroon, Niger, and Nigeria. The lake's first human presence dates back to the Paleolithic era. The Romans later arrived in the lake during Caesar Augustus' rule in the 1st century AD. The most important history of the region began with the emergence of the Sao civilization, which flourished in central Africa from the 6th century BC to the late 16th century AD around the Chari River and surrounding Lake Chad. Artefacts discovered during archaeological digs at Sao culture sites demonstrate continuous hunting and fish-processing practices, such as ceramic fragments, metal implements, fishing equipment, and even conventional boats.