In the heart of Zaragoza, the Aljafería Palace was the 11th-century fortified Moorish castle. The formidable defenses are well preserved, with remains of immense towers that once surrounded the castle. 

The castle was designed on a quadrangular plan around a courtyard, and the towers are all round except for a single rectangular tower, known as the Troubadour's Tower. The Islamic-style coffered ceilings and plasterwork ornamentation give the building its charm.

Today, the Palacio de la Aljafería houses the headquarters of the Aragonese Parliament. The palace is open to the public daily from April through October and Saturday through Wednesday the rest of the year. Guided tours are available.