The monumental black-basalt walls of Kayseri castle were first constructed under the Roman emperor Gordian III and were rebuilt by the Byzantine emperor Justinian 300 years later. The imposing edifice you see today, though, is mostly the work of 13th-century Seljuk sultan Alaattin Keykubat. The castle is undergoing a mammoth restoration project, which will transform its internal area into a museum, art centre and park.
