This is an international-grade wetland situated at the estuary of the Zhengwen River. From the north, it starts at the Guosheng Lighthouse (Qigu Lighthouse) on the Dingtoue sandbank, the south bank of the south dike, and Qigu dike in the reclamation. To the south, it touches the Qingcaolun dike on the south bank of the Zhengwen River. In the east, it borders Guosheng Bridge along the Provincial Highway No. 17. In the west, it extends to the 6m depth contour in the waters. Totally, it occupies a total area of 3,218 hectares.