Diocletianopolis, Thrace

Diocletianopolis was a major Roman city in Thrace, now the town of Hisarya in central Bulgaria [1] [2]. The site has been inhabited since around 6000 BC [1] [3]. Under Rome, the settlement was called Augusta and became one of Thrace's three most important cities [1]. Emperor Septimius Severus visited, and in 293 AD, Diocletian renamed it after himself [1] [3]. The city featured elaborate thermal baths fed by natural hot springs [1]. After the collapse of the northern frontier, Diocletianopolis was destroyed during the Slavic migrations by the early 7th century [1] [4].