Tours to Son Doong Cave in north-central Vietnam will be suspended from now until the end of February next year, the firm that operates the tours announced on Friday.
“Fast-flowing rivers can be very dangerous for visitors during this rainy season,” Nguyen Chau A, director of Oxalis Co., which is currently the sole agency bringing tourists to the grotto, explained the reason for the suspension.
Son Doong Cave is located in Phong Nha-Ke Bang National Park in Quang Binh Province.
“Moreover, our break time also allows the forest ecosystem to recover its flora and fauna as well as water resources,” A added.
In 2014, there were 243 tourists visiting the cave. At the end of August this year, this number reached 482, including 47 Vietnamese.
There are currently nearly 500 awaiting visitors who wish to explore Son Doong Cave, filling the 2016 tour schedule.
The fossils in Son Doong Cave. Photo: Ryan Deboodt
Other visitors will have to wait for their turn in 2017.
According to the People's Committee of Quang Binh, Oxalis Co. is permitted to arrange for a team of 10 tourists at most to visit Son Doong Cave during five days and four nights for the 2016 tours.
The adventure tours are considered highly difficult, during which visitors will have to walk nearly 60km, not to mention other activities such as climbing, crossing the forest, and wading through the streams.
The “pearl” of Phong Nha-Ke Bang National Park, Son Doong Cave, which has a large, fast-flowing underground river inside, was found by a local resident named Ho Khanh in 1991.
It became public after a group of British scientists from the British Cave Research Association, led by Howard and Deb Limbert, conducted a survey in Phong Nha-Ke Bang, a UNESCO World Heritage Site, in April 2009.
A spectacle in Son Doong Cave. Photo: Ryan Deboodt
According to the Limberts, Son Doong Cave is five times larger than Phong Nha Cave, previously considered the biggest cave in Vietnam.
The biggest chamber of Son Doong is more than five kilometers long, 200 meters high and 150 meters wide.
With such large dimensions, Son Doong overtook Deer Cave in Malaysia to become the world's largest grotto.
Hundreds of thrill seekers, mostly foreigners, are currently in line for an adventure expedition, which costs between US$3,000 and $6,000 each person, to the awe-inspiring cave.