Deep in the teak forest in Phu Hoa commune, the southern province of Dong Nai, lies one of Southeast Asia’s longest volcanic cave systems that has remained untapped despite its extraordinary significance.
The discovery was made by explorers from the German Speleological Federation and experts from Vietnam’s Institute of Tropical Biology, who surveyed a cave network in the Phu Hoa commune, which was formerly part of Tan Phu and Dinh Quan districts. Their findings revealed that Doi (bat) Cave stretches up to 534 metres, including collapsed sections, with its longest continuous passage measuring 426 metres. At its widest point, the cave reaches four metres high and ten metres wide.
The La Nga Agricultural Seed Station manages the teak forest sheltering the cave. Planted in 1958 on 165 hectares, the forest was originally intended to supply wood for gunstocks and reforestation projects. Locals later named the site Bat Cave, owing to the thousands of bats inhabiting its dark chambers.
The cave system is in an arched formation, with colourful rock layers in predominantly brown hues forming the ceiling near the entrance. Some passages feature low ceilings that barely touch visitors’ heads.
Ho Huu Duc from the La Nga agricultural seed station said that the cave was once a shelter for Vietnamese soldiers during the resistance war against the US. After national reunification, settlers discovered several cave entrances, but few dared to go deep inside due to the narrow passages and lack of oxygen.
Apart from large bats, the cave system hosts spiders, centipedes, scorpions, and crickets, among others. Local authorities and conservation groups have urged residents not to enter the caves to hunt bats, stressing the importance of protecting biodiversity.
Several cave specialist teams have conducted site visits and proposed collaborative tourism development projects focused on cave exploration. However, local authorities and relevant agencies have yet to reach a consensus on comprehensive planning for the exploitation and conservation of this remarkable volcanic cave system./.
