Aydin was called Güzelhisar ("Beautiful Castle") under the Turkmen Mentese emirs in the 13th century. Renamed for the 14th-century ruling dynasty of Aydin, it was annexed to the Ottoman Empire about 1390. Timur (Tamerlane), who conquered it in 1402, reestablished the principality of Aydin; but it was soon recaptured by the Ottomans. The city was heavily damaged in September 1922 when the retreating Greeks set it afire as a final gesture before they surrendered to the Turkish nationalists. The city's historical buildings include mosques and a theological school. A Roman gymnasium (4th century BC), a marble column, and the theatre are the only remains of Tralles.