Las Médulas, located in the north-west of Spain, is the remains of the largest open-pit gold mine of Antiquity, exploited by the Romans from the first century AD. This site is characterized by red cliffs, hollowed hills, and a network of cavities that form a mineral labyrinth, a landscape shaped not by natural erosion but by human activity. The Romans used a technique known as ruina montium, which involved releasing water from reservoirs to fracture the rock inside the mountains. This process relied on a vast network of canals, called corrugos, and a workforce of slaves and free workers subjected to extreme conditions, as described by Pliny the Elder and Diodorus of Sicily. It is estimated that more than 90 million cubic meters of materials were extracted from the rock during this exploitation. To prepare for the mining operation, more than 3,000 hectares of forest were deforested, a considerable environmental sacrifice carried out centuries before the concept of measuring human impact on natural landscapes was considered. The technique of ruina montium involved digging tunnels and galleries inside the mountain, storing water in reservoirs, and then releasing it all at once to fracture the rock. This method created enough pressure to cause the mountain to collapse suddenly, turning into a mass of mud and rubble, which was then transported through canals for processing. The mining workforce included slaves, but relied largely on free workers who were forced to pay tribute to Rome through their labor. Pliny the Elder described extreme working conditions, including suffocating fumes, rocks broken with hammers, and materials transported on the backs of men in almost total darkness. Diodorus of Sicily, a century earlier, spoke of even harsher conditions, with many miners dying underground due to the brutal nature of the system. The history of the transformation of this territory began long before the Romans, as early as the Neolithic period, more than 6,000 years ago, with an initial deforestation linked to agriculture and livestock. The arrival of the Romans only accelerated and intensified this phenomenon. The result of these millennia of human intervention, crowned by ancient mining, is a landscape that natural erosion would never have been able to produce alone. The red, jagged cliffs, the hollowed hills, and the labyrinthine cavities that make up this scenery are the scars of an industry nearly two thousand years old. Las Médulas is not only an abandoned mining site but also a raw testimony to Roman ingenuity and brutality, forever engraved in the rock. It serves as a striking reminder that some of the most spectacular landscapes on our planet owe nothing to the randomness of nature but everything to the determination, sometimes merciless, of civilizations that preceded us.