Son Doong, the largest cave in the world, is already completely booked for 2026 and 2027, making it one of the hardest adventurous trips to reserve worldwide.
Even though the 2026 season is anticipated to start in late January, all 1,000 available slots have already been taken, said Nguyen Chau A, founder and chief executive officer of Oxalis Adventure, the only company authorized to run this expedition tour.
He said that the 2027 booking list has also been filled.
The world’s largest cave
An entire 40-story New York City skyscraper could fit inside the cave’s enormous main passage, which spans more than five kilometers and has sections that are up to 200 meters high and 165 meters wide, according to Travellive.
In 2015, Son Doong was recognized as the world’s largest cave by the Guinness World Records.
Son Doong expedition tours run from January to August, according to Vietnam News.
Each expedition tour is restricted to less than 10 guests, and the annual total of visitors is not permitted to surpass 1,000 due to stringent laws aimed at protecting the cave’s pristine ecosystem.
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Trekking expertise and physical fitness requirements
Visitors must also meet strict requirements for trekking expertise and physical fitness.
Son Doong is located approximately 25 kilometers from the closest road in Tuong Trach Commune, deep into the core zone of Phong Nha-Ke Bang National Park.
The route is difficult, passing through rivers and forests and traversing intricate cave networks.
The area is under strict protection and is not accessible for independent travel.
Increase in jobs and profit
Tours contribute to forest protection and create jobs.
Since it opened to the public on August 1, 2013, 8,552 people have visited Son Doong.
Vietnamese tourists make up the largest group with 3,293, followed by American visitors with 2,271.
The expedition tour has generated an astounding $25.5 million in revenue since its launch, according to Vietnam News.
The operating company has given Phong Nha-Ke Bang National Park more than $5 million in fees to contribute to forest management and protection.
This tourism model also tackles social welfare issues and helps communities in the buffer zone develop sustainable livelihoods by generating 130 direct jobs for local workers and hundreds of indirect jobs through supporting services.
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