Phu Suan Sai National Park

Phu Suan Sai National Park covers about 73,225 rai of dry evergreen and mixed deciduous forest in Na Haeo district, Loei province, right along the Thailand-Laos border. It was established in 1994 as Na Haeo National Park and renamed Phu Suan Sai in 2006 after the mountain that dominates the park’s skyline. Entry is 100 THB for foreign adults (50 THB children) and 20 THB for Thai adults (10 THB children), daily 08:30–16:30.

The park’s main draws are its waterfalls and rock formations rather than a single big attraction: Namtok Chang Tok, Namtok Wang Tat, Namtok Tat Hueang, and Namtok Pha Kho are the named falls, alongside limestone rock gardens known locally as Hin Si Thit and Hin Kuai Lo. Marked nature trails connect several of these points, running through dipterocarp forest where hornbill calls carry through the canopy — a genuine highlight for birdwatchers, even without a guided count of species.

Insider Tip: Cool-season mornings (November–February) bring a sea of mist over the valleys below the ridgeline viewpoints — arrive early, before the sun burns it off.

Watch out: this is a genuinely quiet, lightly developed park. Facilities are basic and mobile signal is patchy in places, so bring cash for the entry fee, download offline maps in advance, and don’t rely on finding a shop once you’re past the checkpoint.

Bring sturdy footwear, water, and layers — mountain mornings here get cold enough for a jacket even though Loei’s lowlands stay warm. It suits travelers building a longer Loei itinerary around Phu Ruea National Park or the riverside stretch near Chiang Khan, rather than a quick add-on to a Mekong day trip.