The Rhododendron Trail (from Km 10 on the road) leads to the upper reaches of a spectacular waterfall; it's 689 steps down for a dip. The Five Lakes Trail passes pools for swimming before reaching a much smaller waterfall. The short Summit Hike leads to a viewpoint with magnificent views (on a clear day) over the forest, Cau Hai lagoon and the coast. Unexploded ordnance is still around, so stick to the trails.
As most of the park’s resident mammals are nocturnal, sightings demand a great deal of effort and patience. Birdwatching is fantastic, but you need to be up at dawn for the best chance of glimpsing some of the 358 species logged, including the fabulous crested argus pheasant. It's hoped elephants will return to the park from the Lao side of the border.