Formerly, the park was the battle field between the Thai government and the Communists. Its topography is mountain ranges comprising several important tops. The mountain ranges run from east to west and are the origins of several streams. Phu Lom Lo is the highest mountain with a height of 1,614 metres above sea level and is a challenge to adventurers especially in the rainy and cool season. The Than Phayu viewpoint near the Forest Guard Unit at Ban Thap Boek commands a breathtaking view of the sea of mist there. This is one of the best places to see the sea of mist in the lower northern part of the country.