Son Doong Cave
The festival, which was launched in 2014, took place on March 4-6 at the DGA Theater in New York, attracting 150 films from 19 countries.
After the film won the award, the film crew shared pictures of the award ceremony and compliments on Son Doong on their Facebook pages.
Son Doong Cave in the Phong Nha - Ke Bang National Park of Bo Trach district, Quang Binh province, was discovered by a local man named Ho Khanh in 1991. In 2009, a group of British explorers led by Howard Limber conducted a survey and then announced that it was the world's largest cave.
Son Doong is more than 200m wide, 150m high, and about 9km long. It also houses a jungle and a river, and could fit a 40-storey skyscraper within its walls.
It was recently suggested by the American news website huffingtonpost.com as one of the places to visit. Son Doong was also listed in the "52 Places to Go in 2014" by New York Times travel.
Last May ABC broadcast live from the Son Doong cave on the program Good Morning America. The program attracted millions of viewers around the world.
What the stars mean:
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