Earliest Palaeolithic tool industry in the Nok valley

Gravels in the oldest infill of a buried channel in the Nok valley yielded large numbers of bifaces and cleavers of an Acheulian/early industry. A radiocarbon date of "more than 39,000 years before the present" was obtained for carbonized wood from these gravels. This is among the oldest dated evidence of human activity in the central Nigerian area.