Province of Pesaro and Urbino
Monte Nerone (1,525 m) is a limestone massif rich in karst phenomena: caves, sinkholes and deep gorges. It is one of the favorite destinations for speleologists, with cavities such as the Grotta delle Tassare. On the eastern side, the suggestive Fosso dell'Eremo offers excursions among waterfalls and pools. The summit offers views of the entire central Apennines.