Phong Nha Cave
| Phong Nha Cave | |
|---|---|
Phong Nha Cave  | |
| Location | Vietnam | 
| Depth | Unknown | 
| Length | 7729 | 
| Discovery | unknown | 
| Entrances | 2 (river opening and ending) | 
| Difficulty | Dangerous | 
| Hazards | underground river | 
| Access | by Son river | 
| Cave survey | Unknown | 
Phong Nha Cave is a cave in Phong Nha-Kẻ Bàng National Park, a UNESCO World Heritage Site in Quảng Bình Province, Vietnam. It is 7,729 metres long and contains 14 grottoes, as well as a 13,969 metre underground river. While scientists have surveyed 44.5 kilometres of passages, tourists are only allowed to explore the first 1500 metres.