Tsuru Shima (鶴島) is part of Okayama Prefecture, Japan. It is a small, uninhabited island located in the Inland Sea of Japan, hidden from the land by the much larger Kakuijima, and approximately 6 km off the border of Hyōgo and Okayama prefectures. During the early Meiji Period the island was used as a penal colony for Christians.[1] The name means literally "Crane (bird) Island". | ||||||