Southeast Asia’s largest volcanic cave deeper than thought

The new passage stretches 175 meters long, raising the total length of C7 Cave to 1,240 meters.

C7 is one of 50 caves in the Krong No volcanic cave system in Dak Nong UNESCO Global Geopark in Dak Nong Province.

The finding was made after five days of research as part of a sideline activity of the 20th International Conference on Volcanic Caves (ISV) on Nov. 22-26 in Dak Nong, the park’s management board announced Tuesday.

In 2014, a group of Vietnamese and Japanese scientists identified C7, with a length of 1,067 meters, as the largest volcanic cave in Southeast Asia.

As planned, researchers will return to the cave to build a 3D map for it later.

Stretching 25 kilometers long, Krong No is a cave system of basaltic rocks formed from lava eruption. It is yet to be open for tourism.

Dak Nong UNESCO Global Geopark covers an area of 4,760 square kilometers, stretching across five districts of Krong No, Cu Jut, Dak Mil, Dak Song, Dak Glong and Gia Nghia Town. It was recognized by UNESCO as a global geopark in 2020.