The largest cave in the world

Son Doong cave is the world's largest cave, located in Phong Nha-Ke Bang National Park, Quang Binh province, Vietnam. Son Doong Cave was discovered in 1991, but it was not until 2009 that explorers discovered the entire length of the cave. Son Doong Cave is 5,600 meters long, 200 meters high and 150 meters wide, 200 times larger than the world's second largest cave, Deer Cave in Malaysia. Son Doong cave is also the only cave in the world that has an underground river flowing through