phong nha ke national park / vietnam, 16/11/2017: man standing under a high wall with stalactites inside the giant hang tien cave

16112017 adventure asia bang beauty black caing cave cavern chamber dark exciting experience exploration explore giant hang high inside jungle light man mountain national nha nhake outdoor oxalis park phong rainforest river rock scramble shadow southeast spectacular stalactite stalactites stalagmite standing thrill tien tour tourism tourist travel trip under undergound vietnam wall water