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The Lost Forest World of the World’s Largest Cave.
In 1991, a local farmer by the name of Ho Khanh was walking along a stretch of lush forest within the heart of the Phong Nha Ke Bang National Park in Quang Binh province, near the border between Laos and Vietnam. It was an area that he had passed many times before and he was not paying any particular attention to his surroundings when suddenly the jungle floor opened up beneath him and Mr. Khanh only barely managed to hold on as the ground crumbled beneath him. When he was able to get his bearings, he peered into the gaping chasm that had suddenly appeared out of the thick foliage and saw that there was now a steep drop where he had stood that descended down into darkness. By pure chance and blind luck, this man had discovered an entrance that had remained hidden from man for millions of years into what would turn out to be the largest cave in the world, a behemoth five times larger than the largest known cave at the time.