8 fascinating facts about Sơn Đoòng, the world's largest cave
Sơn Đoòng Cave is part of the cave system of Phong Nha-Kẻ Bàng National Park, located in the former Sơn Trạch commune, in the former Bố Trạch district of the former Quảng Bình province (now Quảng Trị province) in central Vietnam. To date, it is widely regarded as the largest natural cave ever discovered in the world.
1. Sơn Đoòng was discovered because of… rain
Sơn Đoòng Cave was discovered by a local farmer named Hồ Khanh in 1991. According to Hồ Khanh, he was making a living at the time by searching the forest for agarwood.
On one trip he was caught in a heavy jungle downpour. Fearing a flash flood, Hồ Khanh decided to look for shelter. By pure chance, the place he took shelter in was… Sơn Đoòng Cave.
2. Sơn Đoòng went missing for… 15 years
When he found Sơn Đoòng, Hồ Khanh had no idea how valuable the cave was. Not long after that trip, he gave up agarwood hunting and went back to farming.
For the next 15 years, the cave's whereabouts remained in the dark. It was not until 2006, when an expedition from the British Cave Research Association came looking for new caves in Phong Nha-Kẻ Bàng, that Khanh told them his story. That marked the start of the search for the cave he had found years before.
3. Sơn Đoòng could not be found on… Google Earth
However, the search for the long-lost cave did not go entirely to plan. All Khanh could remember was a huge cave with wind blowing strongly around the clock.
Even with the help of state-of-the-art scientific equipment and Google Earth, the expedition still could not locate Sơn Đoòng. It was not until 2009 that Hồ Khanh officially found the cave again.
4. Sơn Đoòng is "more than big enough" to serve as an aircraft hangar
According to geologists, Sơn Đoòng formed roughly 2 to 5 million years ago, when river water flowed through buried limestone along a fault line. The water eroded the rock and carved out the gigantic tunnel we see today.
Sơn Đoòng is huge, with a length of at least 5 km, equivalent to enough room for about 68 Boeing 777 aircraft.
The figure may even be larger: according to scientists, even today's most advanced equipment has not yet mapped the cave's true full length.
5. Sơn Đoòng is called the "Great Wall of Vietnam"
Inside Sơn Đoòng, experts have found sections of immense size. A photo taken by photographer Carsten Peter in May 2010 captured a stretch of passage 91.44 m wide with a ceiling nearly 243.84 m high - large enough to "fit" a 40-story New York building entirely.
National Geographic even noted that the cave is so tall that 25 double-decker buses stacked on top of one another would fit comfortably.
The grandeur and sheer scale of Sơn Đoòng's scenery have earned it worldwide recognition as "The Great Wall of Viet Nam" (meaning Vietnam's own "Great Wall", just as "The Great Wall of China" is China's).
6. Inside Sơn Đoòng, visitors can find their very own… "Garden of Eden"
Sơn Đoòng is famous not only for its colossal size but also for its diverse living landscapes.
Inside Sơn Đoòng, explorers discovered an entire primeval forest with lush vegetation, untouched by humans. Experts have even dubbed the forest inside the cave the "Garden of Eden" in tribute to its stunning beauty.
7. Sơn Đoòng holds "pearls" as big as... baseballs
Another remarkable feature of Sơn Đoòng is its system of stalactites and giant cave "pearls." Shaped by external forces over millions of years, Sơn Đoòng boasts stalagmites up to 70 m tall.
In addition, cave "pearls" (mineral concretions, mainly calcite, that build up around a grain much like pearls in the sea) among the largest in the world have been found in Sơn Đoòng.
Normally, "pearls" of this kind are only about 1 cm in diameter, but in Sơn Đoòng they grow as big as baseballs.
8. Sơn Đoòng even draws supermodels
Thanks to its beauty, Sơn Đoòng draws many tourists, 98% of whom are foreigners. Among them are families who have conquered the cave across three generations, and even celebrities such as supermodel Jasmina Mala (from the Czech Republic) and Crown Prince Ahmed Hamdan (from Abu Dhabi) have explored the world's largest cave in Vietnam.
