Cat Ba National Park is an archipelago located in the north of the Vietnamese seacoast and administered by the city of Hai Phong. It consists of 367 islands in Lan Ha Bay, which adjoins Ha Long Bay, and the largest island is also named Cat Ba with the area of 100 square kilometers. In total, Cat Ba National Park has 17,040 hectares of land and 9,200 hectares of sea. This park has many different ecosystems: mangrove forests, limestone forests, and coral reef.
There is a diverse fauna and flora system in Cat Ba archipelago with 2,320 fauna and flora species, in which there are 60 especially rare species on the endangered Vietnamese Red List. The Cat Ba langur resident in the park is listed as a critically endangered primate and only resides in Vietnam. Cat Ba National Park is also renowned because of the archeological research that revealed that maybe humans have lived in these islands for more than 6,000 years.