Trang An which was recognized by UNESCO as A World Heritage Site in 2014. Trang An is of global significance as an outstanding humid tropical tower-karst landscape in the final stages of geomorphic evolution. It is composed of a variety of classical karst cones and towers and a network of enclosed depressions connected by an intricate system of subterranean waterways, some of which are navigable by small boats. The area is unique in having been invaded by the sea several times in the recent geological past but is now emergent on land. The blend of towering mountains draped in natural rainforest, with large internal basins and narrow cave passages containing quietly flowing waters, creates an extraordinarily beautiful and tranquil landscape.