Castillo de Aguilar is known from at least the 9th century. It is mostly in ruin, a part turned into a cistern for the local aqueduct. In the 9th century Aguilar de la Frontera became the headquarters of the rebel Umar ibn Hafsun, who built extensive fortifications and reinforced the castle. However, in 891, Umar ibn Hafsun lost the town to emir Abdallah ibn Muhammad of Córdoba. Due to its strategic position, it was contested and, after the dissolution of the caliphate of Córdoba, it became part of the cora of Cabra.
In 1240 it was conquered by the Christians, although numerous Muslims were allowed to remain. King Peter I of Castile assigned its seigniory to Alfonso Fernandez Coronel, but later reannexed it to the crown. The town was renamed Aguilar of the Frontier due to its position on the border with the Moorish Kingdom of Granada.
Since the mid-seventeenth century the castle was no longer needed for defense, consequently in 1860 it was converted into a Hospital. The Lisbon earthquake in 1755 caused part of the building to collapse. The fallen stones were reused for various public and private works. The remains of the castle are located on the hill to the north of the town on the extension of Calle Villa. The Tourist office is located at the castle. Free guided tours available on request.
References:The Basilica of Santa Maria in Trastevere is one of the oldest churches of Rome. The basic floor plan and wall structure of the church date back to the 340s, and much of the structure to 1140-43. The first sanctuary was built in 221 and 227 by Pope Callixtus I and later completed by Pope Julius I.
The inscription on the episcopal throne states that this is the first church in Rome dedicated to Mary, mother of Jesus, although some claim that privilege belongs to the Basilica di Santa Maria Maggiore. A Christian house-church was founded here about 220 by Pope Saint Callixtus I (217-222) on the site of the Taberna meritoria, a refuge for retired soldiers. The area was made available for Christian use by Emperor Alexander Severus when he settled a dispute between the Christians and tavern-keepers.
The church underwent two restorations in the fifth and eighth centuries and in 1140-43 it was re-erected on its old foundations under Pope Innocent II.