The harbour structures that form the subject of this study are some of the best-preserved examples in western Anatolia. A plan of Adramytteion city harbour has been drawn to evaluate the character of the harbour architecture and identify different types of blocks used. Together with geo-radar and geomagnetic survey, these data have been used to consider the construction techniques and phases of the harbour. Dating has been made through comparisons with similar harbours and excavated material from the adjacent town.