Ishigaki Island , also known as Ishigakijima, is a Japanese island south-west of Okinawa Hontō and the second-largest island of the Yaeyama Island group, behind Iriomote Island. It is located approximately 411 km (255 mi) south-west of Okinawa Hontō. It is within the City of Ishigaki in Okinawa Prefecture. The city functions as the business and transport center of the archipelago. The island is served by New Ishigaki Airport, the largest airport in the Yaeyamas.