Phu Wiang National Park

Phu Wiang National Park protects the sandstone hills where Thailand’s first dinosaur fossils were identified, with numbered excavation pits open to visitors along marked trails through the park’s 191 sq km of forest. Entry is 200 THB for foreign adults (100 THB children), 40 THB and 20 THB for Thai nationals, daily 08:30-16:30.

The excavation pits are the reason to come. Several sit within walking distance of each other, showing fossil bone and footprint impressions still embedded in the exposed rock rather than removed to a display case — this is a working palaeontological site, not a reconstruction. The most significant find came from these hills in 1976: a long-necked sauropod later named Phuwiangosaurus sirindhornae in honour of Princess Maha Chakri Sirindhorn, Thailand’s first scientifically described dinosaur species. Researchers have since identified several more species from the wider Phu Wiang fossil beds, including the spinosaurid Siamosaurus and the early tyrannosauroid relative Siamotyrannus.

Watch out: The park entrance fee and the separate Phu Wiang Dinosaur Museum ticket don’t cover each other. The park (run by the Department of National Parks) charges for the excavation pits and trails; the museum, a short drive away and run by the Department of Mineral Resources, charges separately for its fossil casts and exhibits. Budget for both if you want the full picture.

Trails beyond the pits climb through dry dipterocarp and mixed forest to a handful of viewpoints over the surrounding Khon Kaen countryside — modest by northeastern Thailand’s standards, but a genuine break from the flat farmland most of the province sits on. Seasonal streams and small cascades appear in the rains (roughly June-October); the trails are drier and easier underfoot in cool season.

Insider Tip: Visit the museum first if your itinerary allows it — the context on how the Sao Khua Formation preserved these fossils makes the excavation pits themselves considerably more interesting once you’re standing in front of the actual rock.

Best visited November through February, when cooler, drier conditions make the trail walking more comfortable and views from the higher points clearer. The park sits in Wiang Kao district, roughly 80 km northwest of Khon Kaen city — public transport is limited this far out, so most visitors come by rented car or organised tour. For a lighter, kid-focused stop on the drive in, Si Wiang Dinosaur Park has roadside animatronic dinosaur models rather than real fossils.