When measured by cross-section, Hang Sơn Đoòng is the largest cave in the entire world. It was discovered for the first time by Ho Khanh in 1990 but wasn't fully explored until 2009. More recently, it has only been open to the general public since 2013, making it not only one of the largest caves in the world but one of the most recent to theoretically see the light of day.

It's so massive that an entire ecosystem resides inside of its caverns, which is what draws many people to this natural wonder in the first place. With huge cave 'room's that are hundreds of feet in width and double that in height, it's not surprising that tours for Hang Sơn Đoòng book up quickly - but are still entirely worth taking.

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Hang Sơn Đoòng And Its Unique Subterranean Ecosystem

While many people associate caves with unique rock formations such as stalactites and stalagmites, this cave has entire rainforests just waiting to be explored. Thinking about it is almost akin to thinking about an underwater rainforest - something that seems altogether impossible but is quite real. The story goes that when Ho Khanh first stumbled upon the cave, he noticed clouds billowing out of its entrance and heard the sound of running water. Both of these things are indicators of subterranean environments but even after noticing them, Khanh went home and completely forgot about his discovery. It was only when he met Howard and Deb Limbert of the British Cave Research Association that he was encouraged to rediscover Hang Sơn Đoòng, which took roughly a year.

The cave itself is only about 300 million years old, with rock formations that date back 400 million years. While this may sound fairly ancient, it's still relatively new in regard to much of the world's underground cavern systems. The Rao Thuong River is responsible for carving out this massive cave, which runs underneath the Truong Son Mountains.

What Can Be Found In Hang Sơn Đoòng

Visitors to the cave will encounter cave pearls that often reach the size of baseballs, as well as stalagmites that could be comparable to modest city buildings. These have been created from the water that constantly drips from the ceiling in this damp environment, leaving behind mineral buildup. One of the most recognizable features in the cave is the 90-meter tall 'Great Wall of Vietnam,' which is the final wall found at the end of the cave. For comparison, Oxalis Adventure claims that a 40-story skyscraper could potentially fit inside of this cave.

The cave's dolines, which are spaces where the cavern roof has collapsed, allow light sn air to penetrate portions of the cave. This is also where its natural vegetation can be found, which includes native trees and ground-dwelling plants. The scene is altogether otherworldly, with flora a fauna seemingly to thrive in an environment that would otherwise be dark, damp, and devoid of light. Local wildlife such as monkeys, snakes, and birds also make their homes in and around these dolines, giving it a very prehistoric feel.

Touring Hang Sơn Đoòng

There are many, many tours that one might choose to explore the entirety of Hang Sơn Đoòng. From Oxalis Adventures, visitors have a choice of 12 tours in total, each of which ranges from one day to a total of four.

One-Day Tours

  • Tu Lan Family Experience: A general introductory to the cave, including easy exploration, a picnic, various landmarks, and a mini-game. VND 1,620,000
  • Hang Tien Discovery: A challenging hike, swimming pool exploration, and visitation to the Fairy Cave. VND 1,800,000
  • Tu Lan Experience: Action-packed itinerary that includes treks through the Hang Sơn Đoòng jungles and nearby caverns. VND 1,620,000

Two-Day Tours

  • Tu Lan Family Adventure: Hiking, swimming, painting, carving, and camping around the wilderness of Hang Sơn Đoòng. VND 4,950,000
  • Hang Tien Endeavor: A visit to two of the largest caves within Hang Sơn Đoòng. VND 5,850,000
  • Tu Lan Cave Encounter: Exploration of various caves, the karst mountains, jungle, and waterfalls. VND 4,950,000

Three-Day Tours

  • Hang Tien Exploration: Exploration of both wet and dry cave systems, as well as an overview of each unique rock formation. VND 7,650,000
  • Wild Tu Lan Cave Explorer: Exploration of six caves with the help of an experienced crew, as well as swimming or rafting through cave rivers. VND 7,200,000
  • Quang Binh Exploration: A combination of a scenic vacation and cave exploration, suited for those seeking to combine the two. VND 5,600,000

Four-Day Tours

  • Son Doong Cave Expedition: A multi-day exploration of Hang Sơn Đoòng as a whole. VND 58,200,000
  • Tu Lan Expedition: The most challenging hiking tour; features numerous cave explorations as well as an abseil to an underground river. VND 15,000,000
  • Quang Binh Experience: Good for families; features light exploration combined with fun, kid-friendly activities. VND 6,300,000

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