Haijiao (海礁), also known as Tong Island (童岛), Taibujiao (泰簿礁) or Taijiao (泰礁), is located at 30°44'6"N, 123°9'24"E in the northeast corner of Zhoushanqundao (the Zhoushan Islands) and belongs to Shengsi County of Zhoushan city. The name Haijiao literally means 'the ocean reef', and its generally accepted cartographic name of Taijiao literally means 'the extreme reef', a reference to its isolated position on the edge of China's maritime territory.