Kayseri Castle (Kayseri Kalesi) consists of two separate building groups, namely the inner and outer castle. The outer walls of the fortress were built in CE 242 by the Roman emperor, Gordianus III, while the Inner Fortress was built by Byzantine emperor Justiniaus at the beginning of the 6th century. It took on its present appearance mostly during the period of the Anatolian Seljuks, who reinforced the castle against Mongol attacks. In 2008, it was decided to make the castle a culture and arts centre.