Ventana Cave, known in O'odham as Nakaijegel, is an archaeological site on the Tohono O'odham Nation in southern Arizona whose deep stratified deposits made it central to the study of early human occupation in the region. Excavations in 1941 and 1942 uncovered artifacts in a volcanic debris layer with remains of extinct and living animals, leading scholars to define a distinctive Ventana Complex and to debate its relationship to Folsom, Clovis, and the earliest peoples in North America. A later reexamination concluded the layer dated to about 10,500 to 8,800 BP and that disturbance had mixed older bones into later deposits, reshaping interpretation of the finds.