Coos

Coos (also spelled Cos) was a small island in the southeastern Aegean Sea off the coast of Caria in Asia Minor, situated between Cnidus to the north and Rhodes to the south. It is mentioned once in the New Testament, in Acts 21:1, as a port of call on Paul's final journey from Miletus toward Jerusalem. After his farewell to the Ephesian elders at Miletus, Paul sailed straight to Coos, the following day to Rhodes, and then to Patara, where he found a ship sailing to Phoenicia.

Coos was celebrated in antiquity as the birthplace of Hippocrates, the father of medicine, and as the site of a famous school of medicine that continued for centuries. The island also housed a significant Jewish community. The name Coos, from Hitchcock's interpretation, carries the meaning of top or summit, likely reflecting the elevated terrain of the island's interior. Its brief mention in Acts illustrates the island-hopping character of ancient Aegean navigation, with ships making regular stops at known harbors along established coastal routes.