The Roman theatre of Diokaisareia was completely excavated in October 2018. There are two ranks. The upper level was built on a vaulted structure, while the lower level was built into the slope. An inscription of honour on the Proskenium dates the theatre to the reign of the Roman emperors Mark Aurel and Lucius Verus (161-169 and 180 AD respectively).

Diokaisareia (also Diocaesarea) today Uzuncaburç, belonged in ancient times to the priest state Olba, whose residential and capital lay about 4 km to the east. Diokaisereia was a holy place and cult centre of the inhabitants of the Priest state. After the state of Olba became Roman, the cult of Zeus gained in importance and the cult place under Tiberius (14-37 AD) with the name Diokaisareia became an independent city with its own coins.