Bomb craters from the Vietnam War era are accidental experiments. After 50 years. Forest still can't reclaim the compacted soil.
Vinko Rajic, CC BY 3.0
An ecological reset button
Between 1964 and 1973, American forces dropped over two million tons of ordnance on Laos, making it the most heavily bombed country per capita in history. This campaign, part of the larger conflict in Indochina, left behind a lasting record in the soil of the nation. Each explosion acted as a violent ecological reset. A standard 500-pound bomb could create a crater nine meters wide and four and a half meters deep, instantly vaporizing all vegetation.
The immediate blast was only the beginning. The shockwave produced a phenomenon soil scientists call "bombturbation." This process violently displaces and inverts the soil horizons, burying the organic topsoil and bringing sterile subsoils to the surface. The immense pressure compacts the earth at the base and sides of the crater to a concrete-like density. This creates a physical barrier that is almost impenetrable to the root systems of most native forest plants, halting the natural process of ecological succession for decades.
A area of arrested development
Fifty years after the bombing campaigns ceased, the forests in Khammouane and other heavily impacted provinces show a fractured recovery. The craters remain as open holes in the landscape, often colonized by only a few hardy, non-native grasses and weeds. The compacted soil and altered chemistry inside the craters—which can also include toxic chemical residues from the explosives—create a hostile environment for the native forest species that thrive just meters away.
This results in a group of stalled ecosystems. The crater floor, the rim, and the surrounding undisturbed forest each support vastly different plant communities. Some craters hold water, transforming into small, permanent ponds that host aquatic life but prevent terrestrial plant growth entirely. These accidental experiments show the long-term effects of environmental damage. While the surrounding jungle has grown back, it cannot cross the sharply defined boundaries of the craters, leaving a pockmarked area where ecological time has stood still since the last bombs fell.
💡Fun Facts
Laos is the most heavily bombed nation per capita in world history. Between 1964 and 1973, a B-52 bomb load was dropped on the country, on average, every eight minutes.
An estimated 30% of the ordnance dropped on Laos failed to detonate. Up to 80 million unexploded "bombies" (submunitions from cluster bombs) still contaminate the country, posing a lethal threat.
Some locals have adapted the craters for practical uses, turning them into fish ponds, garbage pits, or sheltered vegetable gardens.
The term "bombturbation" was coined by geomorphologist Joseph Hupy to describe the profound, long-term effects of cratering on soil structure, hydrology, and ecosystems.
Accessible 24/7, as these are features of the open landscape.
Admission
Free.
Accessibility
These sites are located in rural, often remote, forested areas and are not formal tourist attractions. Access requires traveling on unpaved roads and trekking through difficult terrain. Independent travel to these specific coordinates is extremely dangerous.
