Son Doong Cave

Son Doong Cave is a well-known sightseeing at the heart of Phong Nha Cave, in Quang Binh Province. Since the British Cave Research Association explored, it opens for the public. The cave is so massive that a 747 airliner could fly through the cavern. A tourist find interesting in exploring trekking straight down the depth of world's largest cave.

The photo courtesy of Tuoi Tre online