Oak Park has had human occupation from about 5500 B.C. to the present day. It lies within a zone including the early Millingstone Horizon and inland Chumash Indians. Indians camped throughout the area as they collected acorns, yucca, and other food. The sites in the area include major villages, smaller camps and several rock shelters. Chumash people lived here for thousands of years prior to European contact. They lived off of trading, gathering and hunting. The Chumash originally settled in Oak Park due to an abundance of natural resources, including fresh water, acorns and rabbit-hunting. It is one of the oldest occupied places in California.