Originallycalled Dry Cave, Tien Son Cave was discovered in April 1935 in thelimestone mountain of Ke Bang. The Phong Nha - Ke Bang Caves consist ofthe Phong Nha Cave system, with 9 caves of various sizes and the VomCave system, with 8 caves of various sizes. Of which, spectacular TienSon Cave is the most magnificent limestone cave in Vietnam and justopened in 2000.  It is about 400 metres away from the famous Phong Nha Grotto and at a height of 135 metres.

TienSon Cave is more than 980 metres long. Going into the cave for about400m, you will see an abyss, about 10m deep. Then comes another part ofthe cave, about 500m long, which is rather dangerous for walking. Atpresent, nearly 400m of the cave have been installed with lightingsystem to make it safe for visitors.

TheCave looks marvelous inside with hundreds of stalagmites andstalactites of different sizes and shapes. Some look like a man or ananimal, and there is one that looks like the Leaning Tower of Pisa inItaly. On the cave ceiling, there are glittering gold and silver-likeveins. Some stalagmites produce an echoing sound when slightly knocked.

LimberHoward, Chief of the British Royal Team of Cave Researchers, whovisited and made studies of the site, said that Tien Son cave may havebeen formed tens of millions of years ago. A river ran through thelimestone mountain and eroded it. Then, huge rocks fell, separated themountain and formed the cave. An underground river ran through thelower part of the mountain, creating Phong Nha Grotto. Thus, Tien SonCave is older than Phong Nha Grotto and they do not link with eachother. Geographical tectonics in Tien Son Cave are rather stable, sothe cave is safe for visitors.

Atthe present, Phong Nha and Tien Son cave always open to welcome tovisitors to discover marvelous beauty and hidden values here.