Nam Nao National Park one of Thailand most beautiful Park covers an area within Amphur Mueang Lom Sak and Lom Kow in Petchaboon provice and Amphur Kornsan within Chaiyaphum province. The park Headquarters is in an unusual and fascinating landscape: deciduous forest dominated by tall pine trees.
The area is mountainous and its forests provide an important watershed for the surrounding districts. The Park covers in total an area of about 966 square Kilometres. The unusual and fascinating Park designated a National Park on the 4th May 1972
Nam Nao National Park covers the border between northeastern and northern Thailand. Its particularly part of the Phetchabun mountainous range running through Chaiyaphum and Phetchabun provinces. Phu Phajit mountain is the tallest in the Park and topography comprises evergreen forests and streams. There are many rivers and streams within this important watershed area Pa Sak River is one of these, it eventually joins the Chao Praya River, others are Pong and Loei rivers and Khon Kaen and Nam Churn streams. All these flow into the Ubonrat Dam.