It was formerly know as an area of Doi Sam Muen highland development project which was initited by His Majesty the King to solve the problem of forest encroachment and poaching, as well as to enhance the lives of the local hilltribe people. As this area is filled with attractive natural condition and virginal forests provided vital watersheds, Huai Nam Dang was declared the 81st national park of Thailand by the Royal Forest Department on 14 August 1995.
Huai Nam Dang National Park covers four districts : Mae Taeng, Chiang Dao, and Wiang Haeng in Chiang Mai province including Pai district in Mae Hong Son province, covering an area of approximately 1,247 square kilometres. Later on it was designated as the National Park for commemorating 100th year establishment of the Royal Forest Department and also for the celebration of His Majesty the King’s 50th year on the throne.
Huai Nam Dang National Park is situated on top of the ridge of hills and the same range as Chiang Dao mountain range. The highest peak-Doi Chang peak (at 1,962 metres above sea level) is the vital source of important streams which flow into the Pai river, Ping river, and Taeng river.
The climate is comfortably pleasant. The average year-round temperature is 20ðc, dropping to 8ðc in October to February and soaring to 12-28ðc on March to April. The wettest months being May to September.
The healthy natural condition of Huai Nam Dang National Park is a matrix of highly diverse habitat types. Main plants found in this park are Hopea sp., Dipterocarpus spp., Tectona grandis (Teak), Pterocarpus macrocarpus, Michelia floribunda, Pinus kesiya, Pinus merkusii, and orchids especially, Dendrobium infundibulum which charmingly blooms during January to March. Many wild animals dwelling in this richest forest are elephants and some rare animals such as Salamanders.