Castelldefels Castle

Castelldefels Castle is a frontier fortress in the town of Castelldefels, near Barcelona in Spain, that was built to defend the frontier of the Carolingian Empire against neighbouring Muslim territories, particularly the Caliphate of Córdoba. The fortress was first recorded in the 10th century, as was the former parish church of St. Mary, contained within its outer wall.

The castle occupies a hilltop to the northeast of the modern town centre and the castle complex includes the castle keep, a church, associated outbuildings, and a cemetery, all contained within a curtain wall. The hill was first occupied in ancient times and archaeologists have excavated remains of a Laietani settlement dating from the 3rd to the 1st century BC, and a Roman villa dating from the 1st to the 6th century AD.

Source: Wikipedia