The World’s Largest Sinkhole Rescues a Forest from Extinction

In many parts of the world, nature has retreated without a word. Forests disappeared, species were hunted, and villages survived on what was left. For years, Phong Nha-Kẻ Bàng followed this trajectory. Then, a shift took place, at first without noise. This change was born with the discovery of an underground world still intact. Little by little, this isolated place became an example. Today, exploration, protection and local life move forward together, driven by a common will.

A region once dependent on hunting and poaching

Before becoming a classified site, the jungle of Phong Nha-Kẻ Bàng was home to only a few furtive species. For decades, the forest served as a refuge for hunters of pangolins, slow lorises and agarwood, a precious wood sold as incense or ornament. Mongabay's account describes this era as a period of silent exploitation, where nature seemed to retreat in the face of human pressures. The villagers lived mainly from the forest, due to a lack of alternative routes, responding to a growing demand linked to the trade in rare plants and exotic animals.

The fate of this region changed in 1990. British explorers, including Howard Limbert, went to a poorly mapped karst area. The adventure begins with rudimentary infrastructure, bags of money carried by hand and a total absence of information on the underground potential of the site. In his testimony for Oxalis, he recounts the astonishment of his team in the face of the gigantic cavities, unusual in their dimensions and still intact. Little by little, the discovery of the caves arouses growing interest. Among them, Sơn Đoòng stands out. It houses the largest underground chamber known to date. Thanks to this particularity, the site ended up attracting international attention.

Sustainable tourism has reshaped Phong Nha-Kẻ Bàng

The arrival of the first travelers gradually transformed the territory. Scientific missions give way to supervised and limited tourist expeditions. The site adopts a model unique in Vietnam. It is based on guided tours, quotas and strict observation of wildlife. Business plays a key role in this transition. She hires former poachers as guides, porters or protection agents. Over time, the traps disappear. They leave room for hiking equipment.

Phong Nha-Kẻ Bàng thus becomes a laboratory for economic reconversion. Local populations are discovering new jobs, more stable and socially valued, linked to accommodation or the management of underground routes. Transformation is not just about revenue. It modifies the relationship with the territory. The inhabitants become guardians of the forest which they formerly exploited. The fauna takes possession of the place. Groups of Hatinh langurs, an endangered endemic species, are reappearing in remote valleys. Certain animals that have been invisible for a long time, such as the saola, nicknamed the “Asian unicorn,” are sometimes observed by automatic cameras or identified by their tracks.

From precariousness to protection, communities on the front line

International recognition strengthens this movement. Vietnamnet announces in July 2025 the official inscription of Phong Nha-Kẻ Bàng and the neighboring park of Hin Nam No in Laos on the world heritage list. This cross-border extension confirms the ecological value of the karst complex, one of the oldest in Asia, formed around 400 million years ago according to UNESCO. This classification is not limited to a heritage label, it imposes principles of conservation, ecological education and cooperation between the two countries.

In this new dynamic, residents occupy an essential place. They protect the forest, accompany visitors and help identify rare species. They also transmit the living memory of the place. From now on, they no longer stay behind. They become the drivers of change. Where poachers opened their passages, today we find footbridges, maps and observation instructions. Above all, a common will is growing to preserve the wealth of a territory that has become alive again.