The Tam Đảo mountain region is protected by the Tam Đảo National Park, established in 1996, which is one of the largest national parks in the country. There are over 20 peaks with the park area, others of note include Thien Thi at 1,375 m, Thach Ban at 1,388 m and Phu Nghia at 1,300 m. Sharp peaks with sloping sides and numerous, deep partitions are characteristic of the topology. The boundary of the national park is located at an altitude of 100 m around the Tam Đảo range. There is a larger buffer zone (which has area of approximately 535 km2) which surrounds the national park which has an altitude below 100 m. Seventy per cent of the area of the park is covered by natural and artificial forest. The natural forest is about 220 km2 and the human altered forest is about 30 km2