AbstractMagnetic and electrical resistivity tomography (ERT) surveys were carried out in the area of a Roman military installation located near the Zeugma archaeological site in southeastern Turkey. Magnetic gradiometer surveys were performed in the northern part of this area and covered 8.52 ha; measurements were obtained using a FM‐36 fluxgate gradiometer on a 0.5 × 1 m grid. The visualized data revealed the general orientation of the Roman military settlement, which appeared as regular structures in the magnetic images. In addition, ERT surveys were performed in some areas that had shown regular magnetic anomalies. Resistivity data were interpreted using the robust inversion algorithm in two‐dimensional and three‐dimensional forms. Resistivity tomography studies showed that the archaeological structures lay close to the surface. There was considerable agreement between the results of the magnetic and ERT survey methods. Trial trenches were excavated in promising areas to test the geophysical results. A range of distinctive elements of military settlement, such as walls, pipes, roads, foundations and also metallic objects (a large assemblage of Roman military helmets and armour) were discovered during the excavations. Copyright © 2008 John Wiley & Sons, Ltd.