Magnetic and electromagnetic surveys at the Akrai archaeological site (Sicily-Italy)

The Akrai archaeological site rises on a plateau to the west of the Palazzolo Acreide municipality (Fig. 1a). Akrai is an ancient Greek city founded in 664-663 B.C. (Fischer-Hansen, 1995), it was destroyed about 1500 years later by the Saracens, abandoned and gradually buried. The historian Tommaso Fazello identified the city’s position in 1558, and Baron Gabriele Judica carried out the first digs. To date, excavations have gradually uncovered some archaeological structures (Fig. 1b) (Chowaniec and Gręzak, 2016) but the exact extent of the city has still not been defined. The geophysical methods are widely employed in archaeological research, they allow detecting the presence of contrasts in the subsoil's physical features in order to identify buried targets linked with the presence of ancient structures or archaeological remains. This study aims to identify and locate subsoil areas containing archaeological remains in the studied site, comparing the results of the different applied geophysical surveys and the site’s archaeological knowledge. Considering the location of the archaeological remains currently found at the Akrai site, in order to verify the existence of spatial continuity between them, it was decided to focus the surveys in two areas located between the “Thesmophorion” and the “Temple of Aphrodite” to the southeast and the “Public Square” to the north (Fig. 1b). The field surveys were performed using magnetic and electromagnetic (EM) methods (Figs. 1c, 1d). This study aims to identify and locate subsoil areas containing archaeological remains in an important site located in south-eastern Sicily (Akrai archaeological site). Archaeological knowledge from the site suggests that the actual extension of the ancient city of Akrai should be greater than what has been discovered so far. Considering the location of the archaeological remains currently found at the Akrai site, in order to verify the existence of spatial continuity between them, were carried out different applied geophysical (magnetic and electromagnetic) surveys. The data obtained from the geophysical surveys have provided essential information to locate and delimit areas of interest where could be concentrate future archaeological digs.