Nam Nao one of Thailand most beautiful Park covers an area within Amphur Mueang Lom Sak and Lom Kow in Phetchabun 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

Topography
Nam Nao 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.

Climate
The mountains and forests create a cooler climate in the Park, particularly during the night and early morning. The daytime temperatures are very pleasant with an average annual temperature of 25 degree Celsius. Rainy season is between July and October. Cold season can be very cold, sometimes even with a frost and temperatures as low as 0 degree Celsius. The coldest month being November.

Flora and Fauna
The forest of Nam Nao contains many different forest types, including dipterocarp, deciduous, evergreen, hill evergreen and pine forest.

In the past the trees of this area such as have been important sources of money for the Thai economy. There are also many medicinal plants and orchids within the forest.

The forest structure within Nam Nao provides good shelter for animals including; tigers, leopard, asiatic black bear, malaysian sun bear, fox, porcupine, wildpig, guar, mouse deer and rabbits. These are distributed throughout the park. You will also notice signs (dung by the roadside) of the forest elephants and if lucky you may see one.

There are over 200 species of birds in the park. When out walking the trails you are likely to see birds such as parrots, hornbills, warblers, babblers and siamese firebacks. You will also encounter some of the 340 or so butterfly species that live in the park.