SIDE sīd’ ĭ (Σίδη). A city in Pamphylia to which a letter favoring the Jews and requesting the return of Jewish renegades who had fled there, was sent by the Rom. consul Lucius in 139 b.c. (1 Macc 15:23). It was located near the mouth of the river Eurymedon, at the site of the modern Eski Adalia. It was occupied by Alexander the Great and later was the site of the sea battle between the naval forces of Rhodes and the fleet of Antiochus the Great, in which Antiochus was defeated. Early in the 1st cent. it was the base for activity by Cilician pirates.

It was particularly known for its harbor complex which is still distinguishable. The ruins, extant today on the original promontory of the city, consist of a wall separating it from the mainland, several protective fortifications and a theater of characteristically Rom. construction. Evidence has been found of an extensive Jewish population in Byzantine times.