2 Best Sights in Si Phan Don and the 4,000 Islands, Laos

You can hike or bicycle to the beautiful Li Phi Falls on the island of Don Khon, where there are five suspension bridges, viewing platforms, and zip lines to get a bird's eye view of these churning rapids. An equally stunning waterfall, Khone Phapheng, is just east of Don Khon on the mainland. Day-trip tours that visit Khone Phapheng are available in Don Khon. Also on Don Khon, and the connected Don Det, are the remains of a French-built railway. Green Discovery Laos arranges activities and tours of Don Khon.

The largest island in the area, Don Khong is inhabited by a fisherfolk living in small villages amid ancient Buddhist temples. The best way to explore is by bicycle—this is a pretty big place. Far less visited than Don Det/Don Khon, it's also a great spot to chill out along the river. A bridge across the Mekong connects Don Khong to the mainland, but it hasn't yet spoiled the quiet pace of the island, which has beautiful rice fields in the interior.