Trang An, the eco tourism attraction located in the East of Ninh Binh, with area of 2000 ha. The area caves Trang An eco belonging Truong Yen Commune, Xuan Ninh, Ninh Hai (Hoa Lu district), Gia Sinh commune (Gia Vien District), Ninh Nhat, Tan Thanh (town, Ninh Binh) , an area of more than 1500 ha was discovered several years ago. In 2001, the cave was discovered by a system works in terms of research scientists and indigenous people.