Breathtaking drone footage shows gigantic Hang Son Doong – ‘Mountain River Cave’ in amazing detail First place in the world for being the largest cave in the world belongs to Hang Son Doong in Vietnam, in Phong Nha-Ke Bang National Park, about 450 kilometers (280 miles) south of Hanoi. It is more than 8.7 kilometers (5.4 miles) long The cave was found by a local […]