Known as Mountain River cave, this is the world’s largest cave. It is so big that it has its own river, jungle and climate. A farmer only discovered this cave in 1990 by chance as he was seeking shelter from a storm.The mystery is especially strong when the caves are underwater.Stretching over 5km with heights reaching 200m, the cave could house a 40-storey skyscraper or park a Boeing 747 airplane.Paintings from the fourth to the 14th centuries give insights into evolving patterns of daily life more than 1,000 years ago—and beat your average museum visit any day.
There are still more wonderlands waiting to be uncovered. The U.S. alone has 55,500-plus caves with more than 1,000 new ones discovered each year, according to the National Speleological Society. Beware, this visit is not for the faint-hearted. It involves 2 days of intense trekking and river crossing. Getting inside the caves, you will need to climb, crawl and swim through underground rivers to arrive at the end of the cave. According to tour company,
