The Hoang Lien National Park is located within the province and was upgraded from a nature reserve in 2006. It covers an area of 24.66 square kilometres (30 km2 is also mentioned in some references) and contains the peak of Fan Si Pan, which, at 3,143 metres (10,312 ft), is the highest peak in Vietnam.
The park contains heavy forests and a rich biodiversity, although because of agricultural production of ginger and other land uses, today only about 12 kilometres (7.5 mi) of the park is forested. 1884 migrating raptors have been recorded in the national park, which is stated to be a rarity in terms of numbers and the species varieties. The area was surveyed by French biologist Delacour in 1929 who had accompanied Theodore Roosevelt to an expedition in southeast Asia. He collected 48 mammal species for the Chicago Natural History Museum although most were shot. Sediments in the park date back to the Mesozoic era, whilst the granite is a Palaeocene intrusion. The northwestern boundary of the national park is made with a rugged boundary of marble and metamorphosed calcium carbonate.