principal city and port of ancient Pamphylia, originally situated on the Mediterranean coast west of the mouth of the Manavgat River, in southwestern Turkey. (The site is now inland.) Though the city was founded by Aeolian Greeks, a peculiar non-Greek language was spoken there. Having a good natural harbour and two artificial harbours for larger vessels, it was the most important port in Pamphylia. Alexander the Great occupied the city (333 BC), and the Rhodian fleet defeated that of the Seleucid king Antiochus III there (190 BC). In the 1st century BC Cilician pirates made Side their chief slave market. The great ruins—excavated by the Turks from 1947 to 1966—cover a large, walled promontory; one of the most prominent remains is a colossal theatre, built upon arches and considered one of the finest in Anatolia. Pop. (latest census) 443.