Thien Duong cave is located in Bo Trach district, Quang Binh province. This cave is discovered by British Caving Association since 2005, and it is evaluated to be the big and beautiful cave in Phong Nha – Ke Bang. Thien Duong cave is a dry cave and there is no underneath river flowing through like Phong Nha cave. According to the judgment of many experts, this grotto is more beautiful and magnificent than Phong Nha and Tien Son cave, therefore, it is named Thien Duong cave. It is 7km to the Thien Duong cave from Ho Chi Minh road (western part) from km 16. About 300m from the cave, there is a rocky part of road, which requires climbing through the sharp rugger rocks. This cave is located in the area of ecological restoring forest, which is in the core limestone of World cultural heritage of National Park Phong Nha – Ke Bang.
According to the preliminary researches of scientists, Thien Duong cave is longer and in larger scale with Phong Nha cave. There are many magical stalactites and rocky shoots inside and the vast area of floor soil is soft soil, which is suitable for discovering. Coming through the forest of hundreds of years, the ancient trees are lining to cover the land from sunlight, and the birds sing in warble way, the squirrels pass the branches crowdedly, etc.
Coming to the gate of the cave, it is very impressive that the gate is enough for only one person to come which is under the large scale of rock, which is about hundred meters of height. There is a slope leading the floor, which is about 15m wide. When the headlight of 1000W is turned on, the light surprise all the people with many stalactites appear. In the height of more than 100m and the width of 200m, people would stand comfortably to enjoy the natural beauty. There are especially some figures, which are the same with the symbols of culture in different areas. From the deep part of the cave, there are many rocky grains gliding like the terrace field. In the middle of the cave, there are the umbrellas, which are like the symbol of paddy crop civilization with many stalactites under the shape of Champak towers.
Coming to the second part of the cave, the ceiling is suddenly tall up to hundreds of meters with different range of pillars. There is also the stalactites pillar, which is about 30 to 60 cm height on the floor of the cave which looks like the Buddha statues. Due to the lack of light, people could not see them clearly, but if they come close to them, they would recognize the shapes like the animals like tiger, elephant, fish, etc.
In comparison with Phong Nha, the stalactites in Thien Duong cave are more various in shapes. People could see a newly created stalactite with the water fume. When coming above, we could hear the sound of grating noise. There are some parts, which will be alighted with the light of lamé, which look like night stars. Most of the soil inside the cave is soft, so it is quite wide and plain. Therefore, people said that if this cave is turned to the meeting hall, there would be no need of air conditioner. Only at the gate of the cave, the temperature would be always 20-21oC even in the heat of 36-37 oC outside.
The deepest part of cave, which is only reachable by the discovery group, has a big stalactites which are not been seen in Tien Son and Phong Nha grottoes. They are the stalactites seed with the color of white, round and as big as the iron coin of 5,000 VND (3cm circumference). They are lining in the straight line on the wide slope of stone of 60cm which is perpendicular to each other and create rocky tanks. There are pure water inside which seem to be ready for the fairy to washing.
Coming to the soil of fault land, the discovery group could not pass over because they were afraid of the instability of the land and there are still many dangerous tumbling holes. So, from the cave gate to this place with only more than 500m length, there are still many particular interesting parts which are not be able to discover.