South of Kong Island (the largest in Laos) are the 4000 Islands, or Si Phan Don in Lao. This area of extraordinary beauty is known for its fine food (especially fish dishes), distinct temple architecture, and warm hospitality. On Don Det and Don Khone, remnants of an early 20th century railway and steamship port can be visited. At Hang Khone village or at the Laos-Cambodia border, local boats can be hired to observe the endangered freshwater dolphins that inhabit this section of the Mekong.

Accessible from the tiny Don Lai Island, which is just 1 km from Don Khone, Som Pha Mit Waterfall is another amazing natural site to visit. Here, you can relax, enjoy the scenery, watch people fish, and enjoy freshly caught Mekong fish. This waterfall is named after a Sacred Buddha image (Pha), which was dropped in the water and never to be found again by the first King of Laos, Chao Fa Ngum, who was travelling through the region by boat.

Many people have erroneously called it Li Phi, which actually refers to the entire 20 km East-West stretch of waterfalls and rapids of Si Phan Don (including both Khone Pha Pheng and Li Phi). The name Li Phi was given to the area because it acts like a giant fish trap (Li) and will kill any of those who dare to navigate it (Phi means ghost or dead person). As suggested by the name, it is important to watch your step and be cautious around the waterfall.