Extending across the seacoast of four towns, Dongzhai Harbour Mangrove Natural Reserve Area is the first mangrove natural reserve in China. The area is located at Dongzhai Harbour northeast of Qiongshan City and extends for 50 km to occupy a total area of more than 4,000 sq ha.

Mangroves are clusters of evergreen shrub unique to tropical and subtropical mud beaches and are known as "the great green wall on the sea". Migratory birds in autumn and winter bring life to the mangrove area, which is also called the "Paradise of Migratory Birds". Visitors can also take a boat to the nearby Wild Pineapple Island to enjoy enchanting views.