Vietnam’s Son Doong cave, the largest in the world, is even larger than it was previously estimated, according to a group of British divers.
The cave was found to be connected to another gigantic cave, Hang Thung, through an underwater tunnel.
Once the caves are officially connected, it will measure an estimated 1.4 billion cubic feet (39,643,585 cubic metres).
“It would be like someone found a lump on top of Mount Everest, making it another 1,000 meters higher. Any cave in the world will be able to fit comfortably inside Song Dong when it's connected, it's just outrageous in size,” one of the organizers of the dive, Howard Limbert, told CNN Travel.
The three-million-year old cave was accidentally discovered in 1990 and was only explored by the British Cave Research Association in 2009. It opened up to visitors in 2013.
The divers will explore it again in April 2020.