Dubbed the "underground royal palace", Thien Duong cave in Bo Trach district, Quang Binh province is one of the most magnificent and magical wonders in the world. Paradise Cave is located at km 16 (nearly 4 km from the edge of the western branch of the Ho Chi Minh Trail), located in the heart of a limestone mountain complex at an altitude of 191m, surrounded by pristine primeval forest of Phong Nha National Park. Ke Bang, a familiar place in Quang Binh tour itineraries Thien Duong Cave has a length of more than 31.4 km, width ranges from 30 to 100m, the widest place is up to 150m; The height from the bottom of the cave to the ceiling is about 60-80m. It is considered by the Royal British Caving Association to be the longest dry cave in Asia, one of the most spectacular caves that the group has surveyed many caves in. world