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

You can hike or bicycle to the beautiful Liphi waterfall on the island of Don Khon, though an even more stunning one, Khone Phapheng, is just east of Don Khon on the mainland. Day-trip tours that include visits to the Irrawaddy dolphins and the mainland's Phapheng fall set out from Don Khon. Also on Don Khon, and the connected Don Det, are the remains of a French-built railway.

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.