Defined towards the end of the nineteenth century by the Greek writer of Irish origins Lafcadio Hearn, a famous connoisseur of Japan, one of "the least-known portion of the Japanese Empire" and still unknown to the main Japanese tourist circuits, the islands of the Oki archipelago, in the Sea of Japan, are located off Matsue, the capital of Shimane Prefecture, and within the Daisen-Oki National Park, of which they form the insular extension.