There are places where the strict control of human presence has, paradoxically, become a blessing for nature. This is the case of the Canjuers plateau in northern Var, a region in southeastern France. Once a military camp established in 1970 and closed to the public since its creation, the area now hosts one of the twelve remaining French populations of the Orsini's viper, a rare and endangered snake species in Europe. The site is also home to ten species of snakes from Provence, four types of hoofed mammals, the wolf and the lynx, and more than a hundred species of nesting birds, making it a significant reservoir of biodiversity in the region. The Orsini's viper, a small and unassuming snake found in several mountain ranges across southern Europe, has quietly disappeared from many areas without drawing much attention. Unlike more visible species whose decline often sparks public concern, the Orsini's viper has declined largely unnoticed, affected by habitat fragmentation, the loss of open spaces it prefers, and the closure of its natural habitats. Today, only twelve known populations of this species remain in France. The Canjuers military camp covers an area of 35,000 hectares, making it the largest firing range in Western Europe. Only 14 hectares are occupied by buildings, with the rest remaining a natural area where human access is strictly limited. Since its creation over fifty years ago, the site has remained closed to the public, a rule that has never changed. This has created an unintentional sanctuary for wildlife, where the noise and cannon fire from military activities deter recreational human presence. Unlike typical nature parks that must manage tourist traffic, hiking trails, and hunting, Canjuers has never had to deal with these pressures. Some areas, used as firing targets, are completely off-limits to both humans and animals, further reinforcing its role as a de facto protected area. The site's managers acknowledge that the protection of wildlife was never a goal when the area was established. Instead, it is the result of military operations and the strict control of access that has created this environment. The plateau is home to ten snake species found in Provence, a rare concentration of herpetological diversity in such a small area. In addition to four species of hoofed mammals, including wild boar, deer, roe deer, and chamois, the area also hosts two large predators—the wolf and the lynx—whose coexistence is uncommon in mainland France. More than a hundred species of nesting birds have been recorded, placing Canjuers among the most significant biodiversity hotspots in the Var department. The case of Canjuers challenges our assumptions about conservation. We often believe that effective protection requires controlled access and deliberate ecological management by experts. However, here, the result has been achieved through purely military constraints—restricting road access for civilians and prohibiting entry into the firing range—without any conservation goals ever being formally pursued. Despite this, the site continues its dual function: it currently hosts about 2,500 permanent staff and up to 10,000 trainees annually, all part of the French and allied forces. This level of activity might seem incompatible with the survival of a species as elusive as the Orsini's viper, yet it has coexisted with it for decades. This unlikely coexistence highlights how the closure of an area, even for reasons unrelated to ecology, can be enough to preserve species that have been lost elsewhere due to intensive agriculture and urbanization. Canjuers serves as a reminder that the best protection for wildlife is not always the one that is explicitly named. Sometimes, simply leaving a territory undisturbed—regardless of the reason—can be sufficient. It raises a compelling question: how many other areas, closed for reasons unrelated to conservation, may today be the last refuge for species long thought to be lost?