The island has an area of 16.2 square kilometers but a population of only about 3,000. Isolated at sea, it was first used as a site of a prison during the Japanese era.
這個面積僅十六．二平方公里，人口只約三千人的島嶼，由於身處外海，與世隔絕，自日據時期即為囚禁犯人之所。