Bring swimming gear, a good pair of sneakers and your camera! The Tham Phu Kham Cave and Blue Lagoon is a short scenic drive from "downtown" Vang Vieng. What you'll find is a small lagoon with beautiful teal waters and a (steep!) climb to cave where you'll see the pictured reclining buddha. Also bring a flashlight if you have one, as you can explore further in this cave with that. Just make sure you have sure footing as it can be wet and slippery inside. It's definitely worth the climb.