During the Roman and Byzantine periods, it was difficult to establish the building because of the big changes underwent. It was situated between the bouleuterion and the theatre which was built 4th century B.C. when is the same time as the founding of the city.
It was consisted of rooms encircling a courtyard surrounded with columns. From this period only the outer walls on the south and east, the remains of the entrance door on the east, and the foundations of the altar in the courtyard are visible.
The remains of the small temple are situated in the north - west corner of the court yard and belonged to the cult of the Roman Emperors. The pool dated back to the Byzantine period lies to the east of the temple.