Karst covers 18 percent of the Earth and is found in all climatic zones. Karst landforms are diverse and abundant, but Trang An, Ninh Binh has a distinctive landscape not found in Vietnam or the world. It is composed of karst towers of exotic shapes with vertical cliffs, combined with fengcong-valley karst landforms covered by thick vegetation of humid tropical forests, mountain-penetrating caves connecting the closed valleys, depressions and wetlands with rich and diverse flora and fauna systems. The outstanding landscape of Trang An is determined by different endogenous and exogenous factors, such as geomorphology, lithology, geochemistry, tectonics, tropical monsoon climate, flora and fauna, karstification and has been reworked by the sea actions ... It is ideally suited for tourism and scientific research needs.