<P> Located near the Laos -- Vietnam border , Hang Sơn Đoòng has an internal , fast - flowing subterranean river and the largest cross-section of any cave , worldwide , as of 2009 , believed to be twice that of the next largest passage . It is the largest known cave passage in the world by volume . </P>
<P> Located near the Laos -- Vietnam border , Hang Sơn Đoòng has an internal , fast - flowing subterranean river and the largest cross-section of any cave , worldwide , as of 2009 , believed to be twice that of the next largest passage . It is the largest known cave passage in the world by volume . </P>
where is the world 's largest cave located
where is the world 's largest cave located
near the Laos -- Vietnam border
near the Laos -- Vietnam border