Which regions of the Apennines have extensive limestone rock outcrops?

Extensive limestone rock outcrops are found in several regions across the Apennine range. According to geological surveys, these large calcareous formations are prominent in the following areas:

• Lazio, Campania, and Puglia: These regions feature significant limestone outcrops, which are often separated by lowland areas composed of shale and sandstone.1
• Calabria and Sicily: Large calcareous rock outcrops are also present in these southern regions, as well as in northern and eastern Sicily.1
• Central Apennines: The central portion of the mountain system is characterized by the presence of limestone and dolomite.2
• Coastal and Allied Ranges: Several allied series of limestone rocks extend toward the coast, including the Apuane Alps, the mountains of the Amalfi and Cilento peninsulas, and the promontories and peninsulas of the Adriatic coast, such as Mount Conero, the Gargano peninsula, and the Salentina Peninsula in Puglia.2
• Plateaus: In Puglia and southeastern Sicily, the ranges are formed by low, horizontal limestone plateaus.3

In these limestone-dominated areas, the landscape is frequently shaped by karst erosion, which creates distinct features such as crevasses worn by water action.3