Hidden in the thick tropical forest of Vietnam is a land of phenomenal caves. Phong Nha-Ke Bang National Park contains the oldest major karst area in Asia; the karst is believed to have formed 400 million years ago, during the Palaeozoic era, With every cave discovery, that cave is considered the largest and longest in Phong Nha-Kẻ Bàng, only to learn later that yet another even more massive cave has been found. This national park is home to the largest cave in the world and is said to be the home of the many of the world’s most beautiful caves. It’s famous for its cave and grotto systems, about 300 caves and grottos, of which only 20 have been surveyed by Vietnamese and British scientists. UNESCO named it a World Heritage Site for its geological values. Spectacular stalactites and stalagmites create an underground fairy-tale-like world where formations look like the caves possess jagged teeth or home to strangely alien trees. Visitors to Phong Nha-Ke Bang National Park most often visit the massive Paradise Cave and huge Phong Nha Cave as seen below. If you don’t expect to ever travel to Vietnam, then here is a virtual trip to see the mysterious and massive world hidden beneath Phong Nha-Ke Bang National Park .

Phong Nha-Ke Bang National Park contains the oldest major karst area in Asia. Protecting those caves is the reason for the park and also why it was named a UNESCO World Heritage Site. This cave is called Thien Duong (Động Thiên Đường) and is over 19 miles (31 km) long. The British cave explorers were so impressed by the beauty of the rock formation inside the cave, they dubbed this place as “Paradise Cave.”

Stalactites, formed by dripping, hang from the ceiling of the limestone cave. The height of underground Paradise reaches 328 to 492 feet (100 – 150 m) wide.

Formations in Vietnam’s Thien Duong Cave. More stalactites and the flowstone which is like a sheet and can be seen on cave floor and walls.

The national park was created to protect one of the world’s two largest karst regions with 300 caves and grottoes.

Traveling inside Phong Nha Cave. This cave, from which the name to the whole system and the park is derived, is famous for its rock formations which have been given names such as the “Lion”, the “Fairy Caves”, the “Royal Court”, and the “Buddha”. This cave is 25,357 feet (7,729 m) long, contains 14 grottos, with a 45,830 foot-long (13,969 m) underground river. The scientists have surveyed 27.65 miles (44.5 km) of grottos in this cave so far; tourists can only penetrate to a distance of 4,921 feet (1500 m).

Left: A linga-shaped stalagmite. Right: “Cyrtodactylus phongnhakebangensis, a recently discovered cave-dwelling species, lives only in Phong Nha Ke Bang park (hence the name).”

Boats for cave-hopping tourists

Tien Son cave aka Fairy-tale cave has no underground river and is a dry cave. It was named Fairy-tale Cave because its inside landscape is similar to something out of a fairy-tales. Tien Son is 980 m in length. A 10 m deep hole is situated 400 m from the entry mouth, then a 500 m long underground cave, dangerous for tourists and open to professional expeditionists only. Thus we are again looking at Paradise as opposed to Fairy-tale Cave.

Entrance and hanging ladders at this Phong Nha-Ke Bang National Park cave.

Explore Phong Nha-Ke Bang National Park. Have you considered living deep in a cave to survive if something catastrophic happened to the world? It would not be the first time that people have hidden from their enemies and their enemies have hidden from them inside the caves, hidden in the tropical forest of Phong Nha-Ke Bang National Park.

The world’s largest cave managed to remain hidden for all this time; it is thought that finding this cave is only scratching the surface. Hang Son Doong has a jungle inside and a skyscraper could fit inside it too. And the end is out of sight. “Like a castle on a knoll, a rock formation shines beneath a skylight in Hang Son Doong. A storm had just filled the pool, signaling that exploring season was coming to an end.”

Outside the Phong Nha – Ke Bang Cave. Wikipedia states, “The main Phong Nha cave includes 14 chambers, connected by an underwater river that runs for 1.5 km. Secondary corridors branch off in all directions. The Outer Cave and some of the Inner Caves have roofs that tower between 25 and 40 meters above the water level. From the 14th chamber there may be other corridors leading to similarly large chambers, but this area proves more dangerous for explorers because of the ongoing erosion of the limestone of the cavern. The Shallow Cave is located 800 meters from the cave mouth, where there is a spectacular landscape of sand and rock. Stalactites and stalagmites jut out like strange trees, exciting visitor’s imaginations.”

Can you imagine a cave that is five times larger than the Phong Nha? Well there is even if Phong Nha cave was once upon a time believed to be the biggest cave in Vietnam.

The path through the jungle leading up to the Paradise Cave.

Who knows what all is still to be discovered in the jungles at Phong Nha-Ke Bang National Park?

Swimming in Phong Nha Cave. According to UNESCO, “The active river caves are divided into the nine caves of the Phong Nha system discharging to the Son River, and the eight caves of the Vom system discharging to the Chay River. The Phong Nha Cave is the most famous in the entire system, with a currently surveyed length of 44.5 km. Its entrance is the last part of an underground river that connects with the Son River and tour boats can penetrate inside to a distance of 1,500 m. Other extensive caves include the Vom cave at 15 km in length and the Hang Khe Rhy cave with a length of 18,902 m.”