In 1919, the French government banned any rebuilding or habitation on nearly 10,000 hectares around the battle-scarred city of Verdun, deeming the area too dangerous and destroyed for human use. A century later, this "red zone," left untouched by humans, has become an unintentional sanctuary for wildlife. The shell craters left by artillery fire have filled with water, creating a network of ponds that now host one of the last thriving populations of the yellow-bellied toad, an amphibian in decline elsewhere in France. The Verdun forest, abandoned since the end of World War I, now shelters more than 13,000 of these toads, thanks to the craters turned into natural water sources. The former military structures in the area have also become a refuge for other species. For example, the underground fortifications that once protected soldiers now serve as winter shelters for bats. During a recent winter survey, 1,800 greater horseshoe bats were recorded in these spaces, a significant number for a species that is sensitive to human disturbance. The yellow-bellied toad, in particular, is an unusual creature. Recognizable by its yellow-streaked belly and gray-brown back, it is among the most threatened amphibians in France, largely due to the loss of wetlands and changes in land use. However, the Verdun forest has become a rare haven for this species, with more than 13,000 individuals living there today. Some areas within the forest, such as the Caurres woods, are especially favorable for the toad, where it is even classified as common, a rarity in most of France. The forest also supports a variety of other wildlife, including crested newts and dozens of orchid species, indicating a rich and unique ecosystem for this part of the country. The creation of this ecosystem was unintentional: when the French government purchased the 14,000 hectares and planted a deciduous forest, it did not realize it was laying the foundation for a rare natural habitat. The red zone of Verdun has become a paradoxical example of nature reclaiming space left untouched by humans. Unlike other areas where wetlands have been drained for agriculture or development, Verdun has remained isolated and undisturbed for over a century, allowing wildlife to flourish. However, this unintended refuge remains fragile. The yellow-bellied toad depends on the continued presence of wetlands, and any changes in forest management or increased human activity could threaten its survival. Newts, which share the same ponds, are already at risk due to the lack of amphibian crossings, which would help them safely cross roads during their seasonal movements. This shows that even in this sanctuary, the balance between preserved nature and human presence remains delicate.