The Son Doong Cave In Vietnam Is So Big, It Has Its Own Weather System

While seeking shelter from a storm, Ho Khanh, a farmer in central Vietnam, stumbled upon a small entrance to what would soon become known as the largest cave system in the world. He reported his discovery to the British Caving Research Association, but it wasn’t until 2009 that the cave was actually explored for the first time.

After the first expedition into Son Doong, the cave was immediately crowned the largest of its kind in the world. Follow along as we share the interesting history of the long-lost cave and how you can explore its depths yourself.

Where Is Hang Son Doong Cave?

Hang Son Doong, which translates to Mountain River Cave, is in Phong Nha Ke Bong National Park in the Quang Binh province of Central Vietnam. The cave is about 30 miles northwest of Dong Hoi, a coastal Vietnamese city.

The History Of The World’s Largest Cave

Son Doong is 3 million years old and 1.35 billion cubic feet long. For context, the cave is so massive a New York City block with 40 skyscrapers could fit in its depths, and a Boeing 747 could comfortably fit in its largest passage.

In 2019, a team of divers discovered that the cave is connected to another cave, Hang Thung, making the cave system even more elaborate — and seemingly endless. The cave is so advanced it even has a weather system, rainforest, and an intriguing display of rare limestone cave pearls.

There is no evidence of the cave having been explored by humans prior to the 2000s, but other forms of life caught on to the magic of Son Doong before we did. Snakes, monkeys, flying foxes, squirrels, birds, and rats have been spotted underground; and seven new species of white, eyeless creatures (think fish, spiders, scorpion, and shrimp) have been discovered there.

How You Can Visit

For $3,000, you can weave your way through the largest cave system on earth. The four-day-long excursion will be an experience you’ll never forget. On your first night, you’ll sleep in Hang En Cave — the third largest cave in the world — and then spend two nights exploring Son Doong. You’ll trek through over 15 miles of jungle and 5 miles of caves. During your expedition, you might stumble upon 400-million-year old fossils, encounter strange, eyeless creatures, see stalagmites over 200 feet tall, and even swim in the inky-black waters of the cave.

Oxalis is the only tour operator that takes people into the cave. The tours are capped at 10 people and run from February to August. Only 1,000 people are allowed to travel through the cave system every year, so book your tour in advance!

To make the expedition run as safely and smoothly as possible, a crew of caving experts, chefs, local guides, and park rangers are present for every single expedition. According to Oxalis, you don’t need climbing or caving experience, but visitors should have recent experience trekking rough trails and camping.

You can reach the entrance of Phong Nha Ke Bang National Park from the small nearby town of San Trach. If you’re traveling from outside the area, you can fly into Dong Hoi Airport, which is about 30 miles south of the park.