The Great Passage Of Phong Nha-Ke
The Great Passage Of Phong Nha-Ke For thousands of years the great cave of Hang Son Doong (also known as Mountain River Cave) has remained hidden from humans, hidden by lush green forrest. Situated in Vietnam’s Phong Nha-Ke Bang National Park, near Laos border, Son Doong remained secret until the spring 2009, when the first …