About the Show
In 2009 a team of British cavers went on an expedition deep in the jungle of central Vietnam. To their amazement they discover an enormous cave which they believe to be the biggest in the world. The team, the first humans ever to enter the cave, travel six kilometres underground until their way is blocked by a gigantic rock face they dub 'The Great Wall of Vietnam'. Now they have returned, but this time with the right equipment to climb the wall and with a geologist and zoologist to discover if this is indeed the biggest cave in the world and what secrets lie deep within.


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