Phu Phan National Park

Phu Phan covers about 660 square kilometres of the sandstone range that separates the Sakon Nakhon basin from the rest of Isan. Its distinctive features are erosional: Saphan Hin, a natural stone bridge formed where softer rock weathered from beneath a harder slab, and Pha Nang Merng, a cliff viewpoint over the plain, along with waterfalls and rock formations through the forest. The range's other history is recent. Through the 1960s and 70s these hills were a base area for the Communist Party of Thailand in the north-east, and the terrain and forest cover made them difficult to clear; the insurgency here ended with the amnesty of the early 1980s. A royal palace, Phu Phan Ratchaniwet, was built at the foot of the range partly as part of the state's engagement with the region. Facilities are basic and the park sees few foreign visitors.

What you actually see

• Saphan Hin - the natural stone bridge left by differential weathering.
• Pha Nang Merng - the cliff viewpoint over the Sakon Nakhon plain.
• The forest range - sandstone hills dividing the basin from the rest of Isan.
• The recent history - hills held by the insurgency until the early 1980s.

When to go

November to February for the weather; waterfalls run from July into November. Trails are muddy in the rains.

Honest expectations

Basic facilities and limited English interpretation. The rock formations are modest rather than spectacular. Few foreign visitors and little tourist infrastructure. Foreign entry fees are higher than Thai.

Nearby

Sakon Nakhon and Nong Han lake are north-east; Kalasin is south-west.