In mid- April 2009, British caving team leading by Howard Limbirt have explored Son Doong Cave in the Phong Nha - Ke Bang World Natural Heritage site, 50km from Dong Hoi, Quang Binh.
At 150m hight, 140m wide, and over 5km long, the cave is believed to be the world's largest cave, almost twice the size of the current record holder.
Discovered by local people in 2008 but the cave had not been entered due to the terrifying wind and noise from the large underground river..
Son Doong Cave located in center of national park, about 6 hours' walk from Ho Chi Minh trail after pass Doong Hamlet, En Cave. The team spent five days exploring the cave. They had to negotiate two underground rivers before reaching the main passage.