Castillo de Berdejo rises from a rocky promontory overlooking the town of Berdejo in Zaragoza, Aragon. Documented from 1131, this fortress played a critical strategic role as a frontier outpost between Aragon and Castile, particularly during the War of Two Peters. The castle features three walls built directly from the cliff edge reinforced with rectangular towers, and a smaller fourth wall with a square defensive tower standing approximately 12 meters high. The site is included in Spain's Red List of Heritage in Danger.
