This Cave Has Its Own Forest, River, and Clouds

Son Doong is the largest cave on our planet. This enormous cave is so vast that it has a completely self-contained ecosystem with its own climate. Hundreds of meters underground, clouds that you would normally see in the sky actually form inside the cave. Son Doong even contains a prehistoric rainforest hidden far below the surface, along with a massive underground river. From transparent fish to colorful monkeys, more than 250 endemic species of plants and animals live in this underground world. Seven new animal species were recently discovered here, found nowhere else on Earth. Stretching nearly 9 kilometers in length, the cave holds around 38.5 million cubic meters of space. Its passages are so enormous that a 40-story skyscraper could fit inside, and its giant stalagmites rise like the towers of an ancient city. Walking inside, it is impossible not to feel as small as an insect. Son Doong also contains rare phytokarst formations that grow toward sunlight like semi-living organisms. Rare cave pearls and many other unique geological formations can also be found here. For nearly 3 million years since its formation, the world did not know this cave existed until it was fully explored in 2009 in Vietnam. Now, it’s time to witness the largest cave on Earth. Individual access is restricted to protect visitors and the fragile environment. Expeditions are operated by Oxalis, the only official tour operator authorized to guide visitors into Son Doong Cave.