The Rock is a 270 m high promontory overlooking Cefalù. Its calcareous composition, with widespread presence of organogenic fossils, hence the name of “pietra lumachella” (“snail stone”), reveals its origin dating back to the Upper Cretaceous Era (100-65 million years ago): then an environment of flat cliffs emerging on the water’s surface. The promontory is probably a marginal outcrop of the Madonie mountain system, as suggested by the limestone rocks of a very similar nature and the vast circulation of groundwater. It is a small yet complete habitat, which saws the presence of endemic flora and fauna: the former is represented by plants typical of the Mediterranean scrub (while conifers and eucalyptus trees are the result of inappropriate planting dating from the late 1960s); the fauna, on the other hand, is made up of birds, including birds of prey, which nest there permanently, along with small mammals, reptiles, insects and even a variety of snail exclusive to this site (helix mazzulli cephaloeditana). The Rock was frequented by man since prehistoric times, as evidenced by the presence of lines engraved in the Grotta delle Giumente [Cave of Mares] and the discovery of a remarkable ceramic fragment of the Aeolian type, “Capo Graziano” (16th-15th centuries BC). However, the megalithic building commonly known as the “Temple of Diana” is undoubtedly the oldest human construction: in a recent survey its entrance resulted in alignment, at the Equinoxes, with the setting sun, as happens for other well-known monuments belonging to the “megalithic” culture. Since ancient times, the Rock has been used for its strategic value: an exceptional observation location, a fortified site and a refuge in case of siege. Following the two possible paths, we find three mighty city walls: one at the entrance, with mighty bastions, a second with massive walls and the third, crenellated and overhanging along the edge of the cliff. At the top of the Rock stands the imposing bulk of the Castle, whose visible structures date back to the Norman-Swabian era (12th- 13th centuries). On the promontory and its slopes, stone quarries and lime kilns were active until the end of the 1960s, which for centuries provided the City, and elsewhere, a valuable building material: the stones of Cefalù.