Si Phan Don (4000 Islands), a laid-back archipelago in the Mekong River in southern Laos, is the ultimate place to unwind. The main tourist islands are Don Det (backpacker hub with a lively vibe), Don Khon (quieter, ideal for families), and Don Khong (largest, most developed). Rent a bicycle to explore the flat trails, past rice paddies and villages. Don't miss the powerful waterfalls: Li Phi Falls on Don Khon and Khone Phapheng Falls, Southeast Asia's widest. For a unique experience, join a kayaking tour to spot the rare Irrawaddy dolphins.

Visit during the dry season from November to April for the best weather. The rainy season can cause flooding and muddy paths.