4.Kosagijima
Kosagijima has the shore of almost pristine wilderness. There are lots of rocks and seaweeds where valuable fish inhabit, also called Setouchi Ecomusium as the best area to observe animals and plants.
In Taisho period (1912～1926), this island greatly prospered in the shipbuilding industry of sailing ships with hot-bulb engines. Nowadays it entertains tourists with art and nature.