Ishigaki Island is about 420 kilometers southwest of the Shouli of Ryuki-domain island and is the main island of the Yasakayama Islands. The name of the Yasakayama is derived from the image of 19 islands of varying sizes, which are arranged like overlapping mountains. Ishigaki Island is about 90 kilometers long and is characterized by mountains, including Yu Maodengyue, the highest of the Ryukyu Islands and 526 meters above sea level.