That Mok National Park

That Mok National Park protects 290 sq km of montane forest in the Phetchabun Range, about 37 km east of Phetchabun town. It’s not free — entry runs 100 THB for foreign adults and 20 THB for Thai adults — and it’s open daily from roughly 06:00 to 18:00. Established in 1998 as Thailand’s 87th national park, it stays well off the main tourist circuit: around 18,000 visitors a year, a fraction of what the country’s marquee parks see.

The park’s two headline waterfalls anchor most visits. Tat Mok Waterfall, the namesake, drops through a series of tiers reached via a roughly 2 km rocky trail; nearby, the Song Nang Nature Trail climbs about 220 metres past a 12-tiered cascade to a viewpoint over the Phetchabun valley. Wildlife includes Asian elephants, gaur, and golden jackals, along with roughly 115 recorded bird species — hornbills, pheasants, and woodpeckers among them — though sightings of the larger mammals are uncommon on a day visit. Streams cut through the forest along most trail routes, giving regular rest stops in the shade.

Insider Tip: Go in the cool season, November to February. Elevation keeps temperatures noticeably lower than lowland Phetchabun year-round, and the cool months add the clearest skies for the valley viewpoints along the Song Nang trail.

Two campsites let you stay overnight — bring your own tent or rent one on-site — with the higher site giving an open view across the valley. A small welfare shop and basic restroom facilities cover the essentials, but there’s no restaurant or lodge-style accommodation inside the park, so stock up in Phetchabun town before heading out.

Watch out: This is Phetchabun’s own national park, not a Phetchabun-area extension of Khao Yai — the two share no border, hub, or shuttle connection, and any page or listing implying otherwise is wrong. Route your visit through Phetchabun town, not via Khao Yai’s gateways in Nakhon Ratchasima or Prachin Buri.

Pack layers regardless of season — early morning and evening temperatures at elevation drop well below what the lowlands feel — along with sturdy shoes for the rocky waterfall trail. For more of Phetchabun’s national parks on the same trip, Khao Kho National Park and Nam Nao National Park are both within the province.