The importance of human activity throughout history in the Las Médulas area is evident from its environmental heritage and so it is essential to understand this within a historical perspective. The hydrographic network, the vegetation, the fauna, the geological formations exploited in Antiquity, etc. correspond to the lines laid down by the ways in which the territory was occupied and exploited over the centuries. These are elements that have to be considered as integral parts of a heritage in which the natural and cultural are inseparable.