The mountains are named after the town
Nakhon Si Thammarat, located east of the range. The highest elevation is the 1835 m high
Khao Luang. This mountain range is a part of the
Tenasserim Hills system. It begins to the east of the
Phuket Range, which runs in the same direction about 60 km further west. Between the ranges there are isolated peaks, the highest of which is 1,350 m high
Khao Phanom Bencha. To the south it is continued by the
Sankalakhiri Range. Several smaller rivers originate in the mountain range, the
Tapi River is the largest by far. Another relatively large river is the
Trang River. The range is in the
Tenasserim–South Thailand semi-evergreen rain forests ecoregion. ==Protected areas==