Oka-Akoko, city in southwestern Nigeria, located in Ondo state. Oka-Akoko is an agricultural trade center for the region; its chief products include cassava, cocoa, palm oil, and kola nuts. The city is well-connected by road to both the Ibadan and Lagos metropolitan areas. Notable geological features of the Oka-Akoko region are the steep-sided, dome-shaped inselbergs (giant outcroppings of rock) that dominate the landscape. In the past these rock outcroppings served as outposts to defend the city. Oka-Akoko lies in the Yoruba cultural region and supports a large Muslim population. Population (1995) 139,600.