Si Phan Don means 4.000 islands in Lao. It is a Mekong river archipelago in the province of Champasak, in the south of Laos. The Mekong is interrupted by the Khone falls, made up of several rapids which prevent navigation. This river archipelago is one of the tourist attractions of the South of Laos. These numerous islands, in reality several hundred, at this place where the Mekong approaches 10 km wide, are small and very often uninhabited.