What is "olorgesailie"

Olorgesailie is a geological formation in East Africa containing a group of Lower Paleolithic archaeological sites. It is on the floor of the Eastern Rift Valley in southern Kenya, southwest of Nairobi along the road to Lake Magadi. Olorgesailie is noted for the large number of Acheulean hand axes discovered there that are associated with animal butchering. According to the National Museums of Kenya, the finds are internationally significant for archaeology, palaeontology, and geology.