Si Phan Don means 4,000 islands in Lao. It is a river archipelago of the Mekong in the province of Champasak, in the south of Laos. The Mekong is interrupted there by the Khone Falls, made up of several rapids which prevent any navigation. This river archipelago is one of the tourist attractions of southern Laos. These many islands, in reality several hundred, this place where the Mekong approaches 10 km wide, are small and very often uninhabited.