Hang Son Doong Cave, Phong Nha-Ke Bang National Park, Bo Trach District, Quang Binh Province, Vietnam

Phong Nha Cave
Phong Nha Cave is also a cave in Phong Nha-Ke Bang National Park, a UNESCO World Heritage Site in Quang Binh Province, Vietnam. It is 7729 meters long and contains 14 grottos, as well as a 13,969 meter underground river. While scientists have surveyed it to a depth of 44.5 kilometers, tourists are only allowed to explore the first 1500 meters. It is the second biggest cave in Vietnam. Before discovery and exploration of Thien Duong Cave, Phong Nha Cave was considered the most beautiful cave in Vietnam.