Jimena de la Frontera castle was originally built by the Grenadian Moors of the Umayyad Caliphate ruling over the area of Hispania Baetica (modern Andalusia) in the 8th Century. It served as one of many castles guarding both the approach to the fortifications around Gibraltar and the Bay of Algeciras where the strategic and important Moorish stronghold and fortress of Algeciras was located.
The fortress was likely built over the ruins of the ancient city of Oba which dated to pre Roman Celtiberian period. Given its strategic location on the frontier of the Gibraltar region, this fortress proved an important Moorish stronghold throughout the Muslim domination of the Iberian Peninsula.
The castle was taken by the Jerezanos in 1430 and retaken by the Moorish Kingdom of Granada in 1451. In 1465, it was integrated into the Kingdom of Castille as the property of the crown.
The outer defenses consist of a long irregular wall that is lengthened in places to adapt to the uneven mountainous terrain. Watchtowers line this wall at regular intervals. The most well known tower is the Torre del Reloj or Albarrán (Clock Tower) and together, the towers have a very effective line of sight and defense forming an easily defensible arch of a fire zone. Various trenches also exist, all dug in different eras.
Inside the walls stands the Alcázar which was built or renovated after the Christian takeover of the castle. the Torre del Homenaje, with its large circular dome juts out of the Alcázar at a height of 13 meters making it the tallest tower of the castle. The inside of the Torre del Homenaje hides an earlier polygonal pattern tower that was presumably built over after the Christian takeover.
References:Duino Castle was built by the Wallsee family in 1389 on the cliffs overlooking the Gulf of Trieste. It replaced an older castle from the 11th century. Over time, the Wallsee family disappeared and the castle, after having been used as a prison, became the residence of the Luogar and Hofer.
At the end of the 19th century it became the property of Prince Alexander von Thurn und Taxis from the Czech branch of the House of Thurn and Taxis. It remains with the family to this day with his great-grandson Prince Carlo Alessandro della Torre e Tasso, Duke of Castel Duino the current owner. The castle has been opened to the public as a museum and park.