You might think which might be the biggest or the longest cave in the world. The longest and the biggest cave in the world lies in Vietnam. Son Doong Cave was discovered in 2009 in Vietnam and it is still the largest cave known to man. In 2009 a British cave explorer found this cave. The cave is around 5.5 meter long and is a huge attraction for tourists.

There are even some facilities inside the cave for tourists who tour the cave. Oxalis has helped a lot to enters into the cave and explore it. San Doong Cave has become a must visit cave for enthusiastic. There are two natural windows in the cave through which light enters perfectly. Majority of the part of the cave is lit up through the window which helps keep the cave bright. An American photographer Ryan who is now living in Beijing, China described the cave as like an extraterrestrial planet