Tham Prathun Non-Hunting Area

Tham Prathun Non-Hunting Area protects a stretch of limestone karst in Lan Sak district, and its headline site is Hup Pa Tat — a “prehistoric forest” valley formed where an ancient cave roof collapsed, leaving a deep, walled sinkhole now filled with Tat fan palms that grow nowhere else nearby. It’s one of Uthai Thani’s better-known “Unseen Thailand” stops, genuinely worth the detour if you’re already in the province rather than a destination on its own.

The main loop is about 700 metres round trip, walking down into the collapsed chamber and back out through a dark passage roughly 50 metres long. Overhead light filters down through the open roof onto limestone walls draped in creepers, and the bats that still roost in the intact side-passages become visible around dusk. Keep an eye on the leaf litter for Desmoxytes purpurosea, the bright pink “dragon millipede” first recorded here and rarely seen outside this specific valley — it’s the site’s minor claim to biological fame.

Watch out: entry is genuinely pricier than most Thai natural sites — 400 THB for foreign adults versus 30 THB for Thai nationals, a wider foreigner/Thai gap than the standard national park rate. Confirm the current fee by phone before driving out, since non-hunting area pricing isn’t centrally standardised the way national park fees are.

Beyond Hup Pa Tat, the wider protected area includes Khong Chai Mountain (353 metres), whose caves show signs of prehistoric habitation — stone tools and pottery shards — and Khao Plara, where a three-hour guided trek reaches a cliff face carrying old rock paintings. Both require more commitment than a casual stop: the non-hunting area office asks visitors to arrange a guide in advance for the Khao Plara trek, and neither site has the marked path or facilities that Hup Pa Tat does.

Insider Tip: the caves and valley floor are shaded but the walk to and from the car park isn’t — bring water and sun protection even though the main attraction sits underground.

For more of Uthai Thani’s forest and wildlife sites, Huai Kha Khaeng Wildlife Sanctuary is the province’s flagship reserve, and both sit within the Uthai Thani area.