In the extreme south of Laos the Mekong river breaks down into a miriad of arms and channels, which surround countless islands and islets. The entire area is very scenic and attracts a large number of tourists, but navigation by ships becomes impossible, especially because the river passes through the Khon Phapheng waterfalls. This is why the French built a railway to bypass this region for the transportation of goods. In the area there is a small population of Irrawaddy (river) dolphins.