The period between 2011 and 2015 represents a phase of intensive exploration for the British Cavers in Quang Binh. Following the global recognition of Hang Son Doong, the team work extended to mapping remote sectors and identifying a variety of new caves. These expeditions were characterized by grueling multi-day treks into the interior and technical vertical explorations near the Laotian border. Supported by Hanoi University of Science, the team successfully surveyed nearly 40km of new passages and uncovered unique geological formations during this period.
The team of fifteen British cavers, three geologists and three hydrologist, continued exploration in many areas. A total of 47 caves were investigated during this expedition.
In Tu Lan Cave System, Hang Hung Ton, Hang Kim, and Hang Uoi were explored. Hang Va, near the exit of Son Doong is an exceptional cave with unique stalagmite formations. Hang Va was later connected to Hang Nuoc Nut, originally explored in 2003.
In the upper part of the Vom System, Hang 35, Hang Ky, Hang Hai Cua, Hang Gio and Hang Trau were explored. In the Phong Nha System, Hang Cua Nho, Hang Hoa Huong, Hang Nuoc En and Hang Minh were explored.
The Xuong Valley area is quite a remote area, taking 3 days trekking to reach the caves. A number of shafts were descended, and Hang Ha Hai, Hang Khe Cung and Vuc Ky were explored. This area may be the source of the Nuoc Mooc resurgence in the Chay River.
Xuong Valley
Key Achievements
- Hang Va: Located near the exit of Hang Son Doong, this 1,686m long discovery is renowned for its extraordinary "tower cone" stalagmites - unique formations 2-3m tall standing in shallow pools. The cave features a high-level traverse requiring 20m of rope and massive 30m wide passages filled with giant gours.
- Hang Kim: An 829m river cave in the Tu Lan area that bypassed the To Mo sump. Exploration required boats to navigate deep-water sections and man-handling gear over jammed trees.
- Hang Hung Ton: A vital link in the Tu Lan system featuring an active lower cave and a dry fossil passage above, connected by a 10m pitch with a "homemade wooden ladder."
- Hang Khe Cung: An active streamway explored for 734m, reaching a depth of 95m, characterized by a wet 20m pitch and thousands of agitated bats.
- Vuc Ky: A complex vertical system explored to a depth of 312.6m and a length of 3,460m. It features the spectacular 90m "Boppidy Bop" pitch and a tunnel containing the "Fish Bowl"—populated by hundreds of blind whitish-pink fish.
- Hang 35: A massive 1,387m cave in Hang Vom System with an entrance climb providing critical data on the ancient drainage of the massif.
- Hang Hoa Huong: A 1,034m cave noted for its massive breakdown chambers and terminal chokes, named after the guide’s wife.
Hung Ton Cave
Hang Khe Cung
In 2014 a group of fifteen cavers investigated many areas. 39 caves were explored.
Beyond the Xuong Valley, 10 new entrances were explored. Significantly Hang May was 1100m long and 200m deep; Vuc Moi was 500m long and 213m deep, and Hang Lan was 123m long and 33m deep. To the west of Road 20, near the village of A Ky, Hang A Ky 1260m long, is very close to the Lao Border, and water resurging here may come from Lao.
Hang Khe Trieng (previously Khe Tien or Trevor’s Cave) was finally explored to a conclusion after 3.3km, and an unusual cave was explored between Khe Trieng and the En Valley. Hang Khe Dung, 1.5km long, was unusual because there was very little limestone in the cave; it is formed mostly in sandstone.
Thach Sinh Linh Dong is a spectacular 130m deep shaft resembling the second doline of Son Doong Cave. Sadly, both passages at the bottom were blocked.
Key Achievements
- Hang May (Cloud Cave): A technical cave 1,100m long and 200m deep. It features a beautiful 50m entrance pitch and massive chambers with legs over 40m, eventually ending in a mud-filled chamber.
- Hang A Ky: A 1,260m discovery near the village of A Ky. This cave is highly significant as it confirms a trans-border system (NOT 100% sure, need check), with water resurging here believed to originate from the Laotian side.
- Hang Khe Trieng: After 17 years since the initial 1997 trek, the team finally completed the survey of this 3.3km system (previously known as Trevor’s Cave), concluding its exploration to a final sump.
- Hang Khe Dung: An unusual 1,500m cave formed primarily in sandstone rather than limestone - a rare geological phenomenon in a region dominated by karst.
