Orthosia (Ancient Greek: Ὀρθωσία) was a town of ancient Caria, inhabited during Hellenistic, Roman, and Byzantine times. It was not far from Alabanda, on the left bank of the Maeander River, and apparently on or near a hill of the same name. Near this town the Rhodians gained a victory over the Carians. It was the seat of a bishop from an early date, and, while no longer a residential bishopric, it remains under the name Orthosias in Caria a titular see of the Roman Catholic Church.
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