Khun Sathan National Park is located along route 1216 between Na Noi and Rong Kwang. With a height of about 1600 and some stunning view points it is said to be a great place for sunrise and sunset. And in between watching stars. There are some basic bungalows and there is an camping ground and tents for rent. As well there is an small restaurant and coffee shop. Be aware that the last 500m is a good but very steep road to the parking area. For more information see : Khun-Sathan-National-Park
Notice that I did not pay any entrance fee, there was nobody enforcing this. But I do not know if this is normal practice here at this National Park.