Castillo de Osuna stands on a commanding hill east of the town of Osuna in Seville province, with foundations dating back approximately 3,000 years to Iberian settlement. Ferdinand III conquered the fortress in 1239, and the Order of Calatrava later fortified it as a strategically important stronghold guarding the frontier with the Nasrid kingdom of Granada. The 15th century saw the castle pass to the Téllez de Girón family, whose descendants became Dukes of Osuna. Scarce remains of Arab origin include sections of rammed-earth wall and two towers, with the Collegiate Church founded by the dukes adjacent to the castle ruins.
