The Red River Delta Biosphere Reserve (established 2004) is a UNESCO biosphere reserve in the coastal region of northern Vietnam. Mangroves and intertidal habitats of the Red River Delta form wetlands of high biodiversity especially in the Xuan Thuy and Tien Hai districts. These wetlands are of global importance as migratory sites for several bird species. The reserve's surface area (terrestrial and marine) is 137261ha. The core area is 14842ha, of which 6278ha is terrestrial and 8564ha is marine, surrounded by buffer zone(s) of 36951ha (18457ha terrestrial, 18494ha marine) and transition area(s) of 85468ha (35447ha terrestrial, 50021ha marine).
