Son Doong, the world’s largest cave in the central province of Quang Binh, will be featured in an episode of British television series Planet Earth III, to be aired on BBC One from Sunday.
Planet Earth III, the final series in the award-winning BBC trilogy, was shot over five years and combines cutting-edge filming equipment to showcase the greatest miracles of life on earth.
The new series will be narrated by 97-year-old Sir David Attenborough, who is considered one of the longest-serving broadcasters in the country.
Georgina Ward, an assistant producer for the Coasts and Extremes episodes of the series, told BBC she spent almost three weeks underground filming inside Vietnam’s largest cave system.
Series producer Matt Brandon said the crew spent 1,904 days filming the Planet Earth III series. “Trekking for two days through the Vietnamese jungle with 500 kilograms of equipment to reach the world’s largest natural cave, Son Doong, where the team then lived for 18 days underground (longer than anyone has ever spent in the cave before),” Matt told BBC.
In addition to Son Doong, other locations across Asia that appear in the television series include the Maldives, Gobi Desert in Mongolia, Yala National Park in Sri Lanka, Sukkur Region in Pakistan and West Bengal in India.
Son Doong in the Phong Nha-Ke Bang National Park has garnered global attention since it allowed entry to visitors in 2013, a few years after the British Cave Research Association explored and declared it the world’s largest natural cave.
The cave is 656 feet (200 m) high and nearly 500 feet (150 m) wide and the average passage size is 220 feet (67 m), according to the Son Doong tourism website.
Authorities only allow up to 1,000 visitors a year due to conservation reasons, and only from January to August.
Trekkers accompanied by a specialist go through unique underground rainforests, kayak in rivers both above and below ground and climb a 90-meter-high wall dubbed "The Great Wall of Vietnam" with ropes and ladders.
Last year, the image of Son Doong appeared on Google's homepage in 17 countries.
Planet Earth is a 2006 British television series produced by the BBC Natural History Unit. The series received multiple awards, including four Emmy Awards, a Peabody Award, and an award from the Royal Television Society.
Ten years later, the BBC announced a six-part sequel had been commissioned, titled Planet Earth II, the first television series produced by the BBC in ultra-high-definition.