Tucked away in Southeast Asia, within the verdant wonderland known as the Hin Nam No National Protected Area, there is a cave called Tham Khoun Xe. Carved out of the rock by the power of the Xe Bang Fai River, it stretches more than four miles end-to-end; averaging 250 feet wide and 185 feet high, it’s one of the largest caves still in the midst of formation. It’s a glorious, beautiful thing. Also, damn near inaccessible to us stateside would-be explorers, because Tham Khoun Xe is located in central Laos.
So until you can go there and see for yourself, watching kayakers navigate through its arches and caverns from the lens of a tailing Phantom 3 Pro video drone is about as good as it gets.