Geomorphology
One can understand the geological framework of the park's mountains by observing the area's orography and landscapes from any of the panoramic viewpoints available from atop the highest peaks. The southernmost elevations, comprising part of the Tuscan-Emilian Apennines and the ridges of Mounts Calvi and Gatta, are steeply sloped and almost completely covered with forests. Deep valleys cut through these mountains and where the cliffs are particularly craggy and the vegetation sparse you can see sandstone outcrops with very well-defined strata. Long-abandoned hamlets and isolated houses can be found amid these dense mountain forests. At the foot of the sandstone hillsides, the forests give way to a patchwork of plots of cultivated land and shrub woods, interrupted every now and then by badlands and long stretches of rock slides, where grey clay rock formations are visible. The main towns, such as Badi and Castiglione dei Pepoli, are located near those areas where the bedrock shifts from sandstone to clay, providing good conditions for settlement: fairly stable terrain, the presence of spring water where the permeable sandstones come into contact with the impermeable clays, gentle slopes that can be cultivated and forests that can be exploited.