Located on the Tonlé San near its confluence with the Mekong, Stung Treng (ស្ទឹងត្រែង) is a quiet town with limited appeal, but sees a lot of transit traffic heading north to Laos, south to Kratie, east to Ratanakiri and west to Siem Reap. Just north of the town centre, a major bridge across the San leads north to the Lao border, while an important newer bridge traverses the Mekong south of town connecting Stung Treng to Preah Vihear and Siem Reap.
Loaded with largely untapped tourist potential, Stung Treng could benefit from the increased traffic if people stuck around. The main attractions are near the Lao border, where you can kayak out to a pod of Irrawaddy dolphins then continue downstream along a pretty stretch of the Mekong dotted with flooded forest. Further north, thundering rapids cascade over the border, a spectacular sight that's a continuation of the huge Khone Falls.