A five-million-year-old underwater cave, 57 new cave entrances and transparent fish and crustaceans were recently discovered around Son Doong, the world's largest cave, and may hold the answer to where the water that created the vast system originated from.
The British Cave Research Association (BCRA) announced the surprise results of their eight-day expedition in Quang Binh Province on June 22.
Photo by Oxalis Adventure