Son Doong Cave

Place remains a mystery

Since it was discovered, Son Doong cave has surprised experts, cave lovers and travel enthusiasts for its beauty. Not only being very large in scale, Son Doong also possesses mysterious and unique beauty. The problem is that Son Doong now needs to exploit it effectively, but still protect and preserve the "treasure".

In Quang Binh which is the most important area for cave exploration in Vietnam, 350 caves have been explored and mapped, including Son Doong Cave, the world’s largest cave.

Journey to the world

Ho Khanh (left) and Howard Limbert (centre) (Photo: Oxalis)

Son Doong Cave is located in the heart of the Phong Nha Ke Bang National Park in Quang Binh province of Central Vietnam.

In , Son Doong entrance was originally discovered by Ho Khanh, who is a local man. While out on a hunting mission, he stumbled across an opening in a limestone cliff as he attempted to avoid the rain. As Ho Khanh approached he noticed clouds billowing out of the entrance, and could hear the sounds of a river raging from somewhere inside the cave. He was afraid and left afterwards without knowing that the world’s largest cave lies inside that cliff.

In , Howard Limbert and his exploration team met up with Ho Khanh and he described the mysterious clouds from a cave with the loud sound inside the cave. Howard Limbert believed that this could be a very huge cave, he asked Ho Khanh to take the team there.

In , Ho Khanh went back to the jungle by himself, and searched until he found the entrance again.

In , a team of British cavers went to the area with Ho Khanh to explore a number of entrances. The first one they saw turned out to be Son Doong. Not only was it a significant cave, but probably the most significant cave in Vietnam and the world. After surveying, they discovered its full dimensions. After further research they established Son Doong to be the largest cave passage in the world.

In , exploration and surveying of the cave was completed, and the National Geographic team visited Son Doong Cave.

In , they produced a documentary and a magazine article. This drew the attention of travellers to Vietnam, who started to visit Quang Binh and Phong Nha. Many documentary films have since been made around the world.

Amazing facts of Son Doong Cave

Structure of the cave

Two large rivers, Khe Ry and Rao Thuong, join together to form Son Doong Cave. The cave follows a large fault line 100m wide, which contributes to the huge size of the passages. The Phong Nha Ke Bang limestone is around 400 million years old, but Son Doong Cave is less than 3 million years old.

New discoveries in underground river inside Son Doong

Vice Chairman of the provincial People's Committee Tran Tien Dung

With the new discoveries during the diving expedition in the underground river inside Son Doong – the world’s largest cave, Son Doong Cave becomes a true mystery to cave experts and scientists.

For over 30 years, the British Cave Research Association (BCRA) has been conducting multiple cave explorations, surveys and researches to study the numerous cave systems present in Quang Binh Province of Vietnam. Inviting the best cave diving experts in the world to dive in the underground river of Son Doong Cave, opens great opportunities to reveal the hidden secrets deep within the underground caves that the cave experts and researches could never explore before.

In 2019, Oxalis Company Limited and the BCRA collaborated with the Phong Nha - Ke Bang National Park Management Board to invite the cave diving experts to join in the exclusive expedition. All the invitees belong to the top five cave diving experts in the world.

The diving exploration team includes: Team Leader: Martin Holroyd - BCRA specialist, three members who have contributed to the rescue of the Wild Boar football team in Tham Luang, Chiang Rai, Thailand in 2018, including Rick Stanton, Jason Mallinson and Chris Jewell. The team l was also accompanied by Laura Jewell, the diving equipment coordinator for the expedition. Along with Oxalis's 25-person logistics team and the most the modern specialised equipment, the team conducted surveys from April 1 to 6, 2019.

This diving expedition opens a new page of exploration about the underground cave system located at a depth of over 90m and creates a new page for cave experts to explore more about the underground caves. In the meantime, Phong Nha – Ke Bang is still a mystery with the explorers, researchers and scientists.

Howard Limbert - Expert of the British Royal Caving Research Association

On this expedition, the cave experts found a new tunnel system at the depth of 60m, the deeper, the wider the underground cave system opens up. This depth is already deeper than the sea level at the diving position. With this new discovery, Son Doong Cave becomes a true mystery to cave experts and scientists. The depth of Son Doong has increased to over 500m in total from Doline 1 to the final passage yet explored.

In addition to the underground river inside Son Doong Cave, the information from the dive experts shows three distinct levels of development in Son Doong Cave. The high dry level and the underground river level, while the diver’s information reveals another level, a deep submerged passage at 93m depth which is actually below sea level.

Son Doong Expedition

Although Son Doong Cave was inspected in 2009 and published as the largest cave in the world from 2010 by BCRA, it was not until August 2013 that the Quang Binh Provincial People’s Committee allowed adventure tours to be conducted in the cave. Oxalis Adventure is the only tour operator that is allowed by the Quang Binh PPC to operate the tour.

With 4 days and 3 nights, the Son Doong Expedition tour has become the most spectacular journey in the region with the price of US$ 3,000 per customer and only 1000 adventurers are allowed to be in the cave from February to August each year. Tours cannot run at other times due to the extreme weather.

After 3 years of running Son Doong Expeditions with normal routes, the tour operator applied for authorisation to climb the Great Wall of Vietnam, previously the end of the tour. Adventurers will hike 25km in total, go through the cave and climb up the Great Wall of Vietnam to exit instead of returning the same way as in the old itinerary. Permission was granted in 2017, and work began to make a route that was safe and easy enough for guests and the porter team to climb. The result was a 15m steel ladder, and two 35m rope climbs.

All are protected with safety harnesses, ropes and fall arrest devices. A team of 9 people ensures the safety of guests when climbing up. This allows the tour to finish by the exit of Son Doong, and be completed in four days. The Son Doong Expedition employs 100 local people as porters, chefs and safety assistants, raising the standard of living of many families in Phong Nha.

Promoting Son Doong Cave’s value

In order to take advantage and promote the values of Son Doong cave, the People's Committee and Tourism Department of Quang Binh province has build a plan to bring Son Doong Cave into the "capital of adventure tourism in Asia".

Director of the Quang Binh provincial Department of Tourism Ho An Phong.

The development of Son Doong cave into the" capital of adventure tourism in Asia "is completely based. Therefore, Quang Binh tourism hopes that this will be a good opportunity to locate Quang Binh tourism in particular and Vietnam in general

The Quang Binh provincial Department of Tourism is implementing a plan to make Son Doong cave an "adventure tourism capital in Asia" to 2030, with a vision to 2050. In 2050, the tourism industry will exploit the western part of Quang Binh with a system of coastal sand and mountain climbing.

However, several times, Son Doong was face with the risk of "expanding commercial exploitation" with the projects of mass tourism development. In order to preserve Son Doong’s values, managers and tourism developers need to be very alert, considering the immediate and long-term benefits, because there are many caves in the world but only one Son Doong.