Sopheakmith is a series of waterfalls where the Mekong plunges over a limestone escarpment on the Cambodia–Laos border, about 60 km north of Stung Treng. At high water, the falls are a foaming, thunderous spectacle; in the dry season, the water level drops and the rock formations are more visible. The pools below the main cascade are excellent for swimming.
The trip there is part of the experience — a longtail boat from Preah Rumkel village passes through some of the most beautiful river scenery in northeastern Cambodia, with forested banks, fishing communities, and the possibility of seeing Irrawaddy dolphins en route. Combined with dolphin watching at Preah Rumkel, this makes a full and rewarding day from Stung Treng.