Geophysical techniques are a core toolkit of modern archeology, thanks to their effectiveness in reconstructing important pieces of evidence for buried ruins, which are relics of the past usage of an inspected site. Some methodological approaches and advancements are proposed for investigating the site of Gela, which was one of the most important western Greek colonies, founded in 689–688 BC on the southern coast of Sicily, Italy. The ancient settlement was developed on a hill, mostly flat on the top, and over its sides. The archeological evidence discovered so far in the acropolis of the city can be attributed to two main architectural typologies: urban blocks and archaic temples. Based on these targets, a geophysical protocol has been tested, utilizing passive seismic, electrical resistivity tomography (ERT), and ground-penetrating radar (GPR) methods. Where the lowest physical contrast was expected among possible archeological remains and burying soil (close to the urban blocks area), the three geophysical techniques have been jointly applied, while an innovative support-to-interpretation approach for GPR datasets is proposed and developed over both kinds of archeological targets. Our experimental outcomes underline the effectiveness (and possible weaknesses) of the two geophysical investigation strategies against various targets producing different signal-to-noise responses, thanks to the synergistic contributions from multi-method and multi-depth approaches. The integrated use of GPR, ERT, and passive seismic methods allowed the reconstruction of complementary information, with each method compensating for the limitations of the others. This combined approach provided a more robust and comprehensive understanding of the subsurface features than would have been achieved through the application of any single technique.

The paper concerns a research project carried out since 2011 by the Department of Sciences on the Antiquity of the University of Messina and the Institute for Archaeological and Monumental Heritage of the Italian National Research Council. The project is aimed at the reconstruction of the ancient topography of the territory of the modern village of Rodì-Milici, in the Province of Messina. The first campaign of systematic archaeological and topographical surveys, using a differential GPS system and a Laser Scanner, were performed in the hills to the west and south-west of the two villages, in particular on the large plateau between Monte Ciappa, to the north, and Pizzo Cocuzza, to the south. The investigated area was identified by L. Bernabò Brea, at the beginning of the 1950s, with the site of the ancient city of Longane. It had a strategic location for the control of the valleys of the Patrì and Mazzarrà rivers (respectively to the east and west of the investigated area) which constituted important routes of connection and traffic between the Tyrrhenian coast, the Monti Peloritani area and the Ionian coast of Sicily. The recent research, in integration with previous studies, acquired new data about the Archaic settlement that had an organisation strictly integrated to the topographical context and a structure different from traditional Greek colonies. The settlement on the plateau did not have a regular plan but seems organised into quite well distinguished inhabited, productive and sacred areas, while other areas are free of structures. It was protected by the two fortified hills (Monte Ciappa and Pizzo Cocuzza) which controlled the natural entrances to the plateau from north and south; the necropolises were located to the north-east and south of these hills, along the principal ways to arrive to the settlement.