Caltabellotta's most significant historical moment came on 19 August 1302, when the Peace of Caltabellotta was signed in the castle at the summit. The treaty ended the War of the Sicilian Vespers — a 20-year conflict between the French House of Anjou and the Aragonese Crown over control of Sicily — and created the independent Kingdom of Sicily under Frederick II of Aragon.
The castle ruins where the signing took place are accessible at the top of the ridge, above the Santuario di San Pellegrino. There is no formal monument to the treaty, which makes the site all the more quietly remarkable: this windswept pinnacle of limestone was once the scene of a peace negotiation that changed the balance of power in medieval Europe. Most visitors who make the climb have no idea what happened here.