The context of early megalithic architecture in eastern Africa: the Turkana Basin c. 5000-4000 BP

Megalithic ‘pillar sites’ built by middle Holocene peoples of the Turkana Basin in northwestern Kenya provide eastern Africa's earliest known example of monumental architecture. Radiometric dates place pillar site construction and use ~5000-4000 cal. BP. This social innovation occurred during a period of marked environmental and economic change: the level of Lake Turkana dropped dramatically, vast plains opened between the lake and neighbouring volcanic ridges and herding was added to the previous local subsistence repertoire of fishing, gathering and hunting. Material culture recovered from the pillar sites suggests that they supported diverse commemorative practices including, but not limited to, the mortuary sphere, and that they may have been built and used by multiple social groups.