Okinawa Prefecture (Japanese: 沖縄県, Hepburn: Okinawa-ken, Okinawan: ウチナーチン Uchinaa-chin) is the southernmost prefecture of Japan. It comprises hundreds of the Ryukyu Islands in a chain over 1,000 kilometres (620 mi) long. The Ryukyus extend southwest from Kyushu (the southwesternmost of Japan's main four islands) to Taiwan. The Okinawa Prefecture encompasses the southern two thirds of that chain.