The World's Biggest Cave in Vietnam

 In 2009, a team of British cavers investigated a recently uncovered cave in a remote Vietnamese jungle. The Son Doong cave is enormous; can it be larger than the current world-record holder? The explorers traveled for miles through the cave before hitting a 46-foot-high wall.

Song Doong aka Mountain River Cave, 
Son Trach, Bo Trach District, Vietnam.