Phong Nha Cave is a natural scenic spot listed as "Cave of the First Wonders". not be back of it. The decent caves are formed to create geological structures in the limestone mountains. The system of faults on the rock surface has allowed water to seep into the rocks. It is famous for a poetic, interesting fairy world. Making stalactites in the cave undergoes years of architecture from water dissolved limestone, thereby accumulating into fancy animals: lion, throne, buddha, ... ... object for visiting customers.