Son Doong Cave, a precious gem deep inside the Phong Nha – Ke Bang World Natural Heritage, has just been described in an admiring article by the leading travel magazine Travel + Leisure (USA) as an “unbelievable natural wonder” – an “underground world” with its own climate, jungle, underground river and even clouds forming right inside the cave.
Son Doong was first discovered in 1990 by a local man named Ho Khanh, who was searching for agarwood near the Vietnam-Laos border. Although he did not go deep into the cave, the cold feeling and the thick fog emanating from the cave entrance left an indelible impression on him. It was not until 2009, with the support of a British cave expedition led by Howard Limbert, that Ho Khanh returned to the exact location, marking an important milestone in the history of cave exploration in the world.
Son Doong Cave continues to amaze the American press with its surreal beauty that is rarely found anywhere else.
The name Son Doong, meaning “mountain and river cave”, was given to this giant cave. At up to 200 meters high, 160 meters wide and nearly 9 kilometers long, the cave is large enough to accommodate an entire city block with 40-story skyscrapers. With an estimated volume of at least 414 million cubic feet, Son Doong was recognized by Guinness World Records as the world’s largest cave in 2013.
What makes Son Doong unique is the distinct ecosystem that has formed inside the cave. Two natural “skylights” on the ceiling, also known as sinkholes, allow sunlight to pass through, creating ideal conditions for a primeval forest to thrive underground. This creates spectacular scenes, rarely seen in any other cave in the world.
Son Doong impresses with numbers such as the cave length of nearly 9km, the maximum height of the cave dome is up to 200m and the maximum width is up to 160m.
Not only does Son Doong have a forest, it also has its own unique climate system, with underground rivers (like Khe Ry and Rao Thuong, which contribute to the formation of geological structures), fog, and even clouds forming right inside the cave. This is proof of a vibrant world with its own rules, hidden deep underground.
This place is also famous for its giant geological structures, typically the nearly 90 m high calcite wall known as the "Great Wall of Vietnam".
Millions of years of tectonic activity have created enormous and impressive geological structures in Son Doong. The most prominent is the nearly 90-meter-high calcite wall, dubbed the “Great Wall of Vietnam”. In addition, there are countless stalactites and stalagmites that are more than 3 million years old, with many majestic shapes, sparkling like natural sculptures. Some other famous spots in the cave exploration journey are the “Dog’s Hand” stalactite or the “Watch Out for Dinosaurs” sinkhole that appeared in the movie Pan and Neverland.
Exploring the magical world of Son Doong is not an easy task. Currently, Oxalis Adventure is the only unit licensed to organize this cave exploration tour. The journey lasts 5 days and 4 nights and is a real challenge that requires physical endurance and experience. Visitors must be between the ages of 18 and 70, able to hike at least 8 km/day continuously for a year, run 5 km within 50 minutes and climb 5 floors continuously without stopping.
Exploring Son Doong is not an easy task. Currently, there is only one unit allowed to organize tours – Oxalis Adventure – with a journey lasting 5 days and 4 nights.
The trip not only includes trekking through forests and wading through streams, but also includes adventurous rope ladders, taking visitors deep into the mysteries of the cave. At a price of 3,000 USD/person, this is a unique experience, one of a kind in the world. The next tour opening date is currently for departures from January 2027, showing the attraction and scarcity of this natural wonder.
With the detailed and impressive descriptions of Travel+Leisure, Son Doong will certainly continue to be the dream destination of explorers and tourists eager to explore the wild and majestic beauty of nature.
