Phong Nha-Ke Bang National Park, 500 km south of Hanoi, is one of the jewels of Quang Binh province. Recognized by UNESCO as a world natural heritage, the park straddles an imposing forested mountain range and some of the world’s most extraordinary caves.

Son Doong cave (Photo: CNN.com)

Recognized as a UNESCO World Heritage Site in 2003 for its ancient karst formations and in 2015 for its biodiversity, Phong Nha-Ke Bang National Park is part of Asia’s oldest karst mountains dating back 400 million years.

More than 80 km of caves have been discovered here. Phong Nha cave is praised for having the most beautiful underground river, the largest cave entrance, the most spectacular underground rock formations, the most impressive underground lake, and the most majestic stalactites. At 8 km in length, Phong Nha is the world’s longest cave.

Many of the caves are open to tourists. Son Doong cave is the world’s largest cave. Hang En cave is the world’s 3rd largest.

The cave’s stalactites are masterpiece of nature’s art.  It is a complicated business to explore these two extraordinary caves. Tourists must bring several items of required equipment.

Dang Dong Ha, Deputy Director of the Quang Binh Tourism Department, says that visits to these spectacular caves is limited and requires assistance from an experienced technical team before being you’re allowed to enter the caves.

Tien Son is one of the most popular caves. It is accessed by climbing about 300 meters above Phong Nha, its twin sister. If Phong Nha resembles a palace at the bottom of the ocean, Tien Son offers the breathtaking spectacle of an underground paradise, surrounded by a lush forest. Tourists who explore these two caves must walk around huge stalagmites.

Tour guide Le Huy Dung said, "In the last six years, tourists have flocked to Phong Nha-Ke Bang. Foreign visitors are particularly interested in the site. They like adventuring in a natural environment for from mass tourism."

Phong Nha-Ke Bang National Park covers more than 340,000 hectares, 83% of which is primary forest. It has a rich ecosystem comprising 2,400 species of plants, many of which are in the Red Book of Endangered Species. Its fauna is also very diverse including hundreds of species of birds, mammals and reptiles, some of which are rare, like the saola and the langur of Ha Tinh.

Not far from the beaches of Da Nhay and Nhat Le and the archaeological site of Bau Tro, Phong Nha-Ke Bang was called by the Lonely Planet Guide, a favorite place of nature lovers.

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