Okinawa is a Japanese prefecture consisting of over 150 islands in the East China Sea between Taiwan and mainland Japan. It is known for its tropical climate, its wide beaches and coral reefs, as well as World War II sites. On the largest island (also called Okinawa), there is Okinawa Prefectural Peace Museum, which commemorates the massive Allied invasion of 1945, and the Okinawa Churaumi Aquarium, which is home to whale sharks and manta rays.
Source: Wikipedia