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Cave Hang-Yong (Hang En Cave), Vietnam
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Cave Hang-Yong (Hang En Cave), Vietnam Going deeper, travelers get to Hang-Yong, cave created by Rao Thuong River (Rao Thuong). Turning into a series of ponds in the dry months, the level of the river can reach 300 feet (91 meters) in the flood season, covering the rocks, which are cavers.
Source: mirfactov.com/