“There was quite a substantial breeze coming out. A substantial breeze normally would signify a substantial cave.” A nice piece of Brit understatement about what is a late-breaking entry for a wonder of the world: Vietnam’s Hang Son Doong, the largest cave system on the planet by volume, stumbled upon by jungle logger Ho Khảnh in 1991 and only surveyed in 2009. The stupefying shots here of towering limestone buttes, skylight dolines and sodden subterranean rainforest look computer-generated, like something from Avatar.
Another visitor points out that where other caves echo each other, Hang Son Doong feels like nothing else on Earth. Predictably, this exceptionalism has dollar signs spinning in the eyes of the Vietnamese government and big business, who are sizing up the grotto for a cable car transit system. Alastair Evans’s slightly ungainly documentary (we only get the history of the cave’s discovery 20 minutes from the end) very thoroughly details the campaign to preserve Hang Son Doong in its natural state in the context of Vietnam’s breakneck economic boom in the period since it was discovered.
