The (Roman) theatre from the 2nd century A.D. was built with its cavea in the Greek-Roman style in a natural hollow of a mountain slope. The lateral wings were built with masonry. It is divided into 2 tiers by a gallery. The first, lower tier has 30 rows of seats, while 15 rows of seats are preserved from the upper tier. Remarkable are the seats of the uppermost row of the first tier carved out of stone blocks. Several earthquakes hit the town and the theatre hard. The stage house, once two-storey, is completely destroyed.

According to tradition, Selge was founded after the war for Troy by the seer Kalchas and settled by Greeks from Sparta. On coins the place is verifiable since the 5th century BC. Economic basis were the cultivation of wine and olives on the surrounding fertile plateau. Politically there were good relations to Aspendos, otherwise the city was warlike against its neighbours. When Alexander the Great travelled through Asia Minor, the city allied itself with him to besiege the nearby town of Termessos, but without success.

In 25 B.C. Selge loses his independence and is incorporated into the Roman province of Galatia. According to Strabo, the city had about 20,000 inhabitants at that time. Selge reached its greatest bloom at the time of the Roman Empire. 339 it comes to an unsuccessful siege by the Goths. In Byzantine times Selge was a bishop's seat. The town was later abandoned in the Seljuk period.