The Curragh was added to Civilization III in Conquests.
Civilopedia Entry
"Curragh" is an Irish name for a small boat made of skin stretched over a frame of wood. The origins of this small boat date back many thousands of years, predating the more sophisticated and larger war galley. In the game the curragh can represent any small boat (papyrus, wooden canoes or rafts, etc.) used by ancient people to expedite movement up and down waterways and along coastal shorelines.