Book excerpt: Wales is essentially an upland country where mountains and moorlands are the dominant components of the rural scene. The form and character of these landscapes are the consequence of a long history of change. Their distinctiveness is the result of complex interaction between the natural environment and human intervention. Based on the results of an archaeological field survey, this book attempts to unravel the many strands in the evolution of one particular upland area of South Wales, Mynydd Du and Fforest Fawr, part of the Brecon Beacons National Park. The history of human activity in this area can be traced back to the earliest stages of climatic warming after the end of the last Ice Age when Mesolithic hunters followed migrating herds onto the less densely wooded high ground. Seasonal visiting was continued by early farmers until, from the beginning of the Bronze Age, more intensive patterns of land use emerged. After the end of the Roman military presence evidence for mainly seasonal occupation once again becomes widespread, during the Medieval and Post-Medieval periods. This was followed by the intensive exploitation of the area's mineral wealth during the Industrial Revolution and after, giving rise to some of the most dramatic features of the present-day landscape.