Castell d'Ascó occupies a commanding position on a hilltop above the town of Ascó on the right bank of the Ebro River, likely dating to pre-Roman times as a watchtower. This structure, designated a property of national cultural interest, served as the residence of the governor of Siurana during the Muslim occupation before becoming the center of a Templar commandery in 1153 following a grant from Count Ramon Berenguar IV of Barcelona. The remaining visible elements include a large square-based tower of Sarraí origin later modified during the Carlist wars, along with segments of medieval fortifications that document centuries of strategic and military use.
