Oku, OkayamaOku was a town located in Oku District, Okayama Prefecture, Japan.PopulationAs of 2003, the town had an estimated population of 19,389 and a density of 282.19 persons per km2. The total area was 68.71 km2.MergeOn November 1, 2004, Oku, along with the towns of Osafune and Ushimado, was merged to create the city of Setouchi.