Among the museums that preserve and serve İstanbul's historical heritage, Kariye Camii contains the most brilliant legacy of Byzantine art. Tekfur Sarayı Müzesi, as the last standing witness of the Byzantine Empire, transports you to the Byzantine period the moment you step inside. Anadolu Hisarı Müzesi preserves a magnificent structure built by Yıldırım Bayezid in 1393-1395. Rumeli Hisarı carries forward to our day the fortress built by Fatih Sultan Mehmed before the conquest of İstanbul. These places are indispensable for understanding İstanbul's multilayered past.