This alliance includes thermophilous oak forests occurring on calcareous bedrock, usually on south-facing slopes. Their tree layer is dominated by Quercus petraea agg. or Q. pubescens agg., less frequently also by Q. robur. The shrub and herb layers are well developed, the latter including many species of dry grasslands and dry herbaceous forest fringes, but also species of mesic forests and nitrophilous herbs. This alliance is distributed in the Submediterranean belt of southern France and on the fringes of the Pyrenees, Alps and Carpathians, and in adjacent areas, including the foothills of the Hercynic mountain ranges north of the Alps.