Sirmium

Sirmium was a major Roman city located on the Sava river at modern Sremska Mitrovica in Vojvodina, Serbia [1]. First mentioned in the 4th century BC, it was originally inhabited by Illyrians and Celts before Roman conquest in the 1st century BC [1]. The city became capital of the Roman province Pannonia Inferior and in 293 AD was proclaimed one of the four capitals of the Roman Empire [1]. It later served as capital of the Praetorian prefecture of Illyricum and of Pannonia Secunda [1]. The archaeological site is protected as a Site of Exceptional Importance, and the modern region of Syrmia derives its name from this ancient city [1].