The theatre was first built in the Hellenistic period (3rdury BC) during the reign of Lysimachos on the slope of Mount Pion, and was later enlarged. The theatre, in which wild animal fights and gladiator games were held in the 3rd and 4th centuries, is the largest theatre structure in Turkey and has a capacity of 24,000 spectators.
The stage-building had three storeys including the ground floor. Only the ground floor has reached to the present and is well preserved. The secrion where the audience sat had a height of 38 meters (114 feet) and a diameter of 158 meters (474 feet).