Abd ar-Rahman II
Located near the Roman bridge over the Guadiana river, the "Puente Romano", it was built by emir Abd ar-Rahman II of Córdoba in 835 to command the city, which had rebelled in 805. It was the first Muslim alcazaba (a type of fortification in the Iberian peninsula), and includes a big squared line of walls, every side measuring 130 metres in length, 10 m of height and 2.7 m thickness, built re-using Roman walls and Roman-Visigothic edifices in granite. The walls include 25 towers with quadrangular base, which also served as counterforts.