Geophysical survey was carried out during July and October, by teams from the University of York and the Institute of Mediterranean Studies respectively. The goal of the geophysical prospections is to supplement and test the results of the surface survey data, by identifying and analyzing sub-surface cultural remains. Consequently we follow the strategy of dividing the fields in squares 20 X 20 m, ideally the same squares that are covered by surface survey.
The University of York team focused on 37 tracts total from all three areas of the plateau, and covered approximately 94,000 sq.m.
Mapping was done exclusively by magnetic survey and the use of a fluxgate gradiometer.
Out of the many human-generated remains that were detected, we shall mention the most representative ones. In the upper plateau, and more specifically in UP25-26, a square building appeared, measuring approximately 10 X 10 m and oriented N-S, E-W.
In the northern plateau we discovered parts of buildings and city blocks, along with four street intersections, which in combination with the surface data help us to reconstruct the ancient town plan. More specifically, in the northern part of the plateau we identified a rectangular building measuring ca. 21 X 10 m, with internal divisions and N-S orientation.
Part of a structure of a city block is also visible in the adjacent squares. Stretches of streets of the ancient city, 5.0 - 6.5 m wide, as well as intersections can be easily made out in many tracts. Their orientation is N-S, E-W, and set the width of the ancient insula to ca. 60 m. The length of the insula according to the data available so far does not seem to have been consistent, but further processing of the data and more fieldwork is necessary in order to draw safe conclusions.
In the southern plateau, we detected parts of city blocks filled with peristyle courts and houses of large dimensions in SP30 and 38, and a stretch of an important E-W street, approximately 6.5 m wide, in a tract nearby.
The next stage in the processing of the geophysical data is their comparison with surface data and artifact densities from the same squares.
The team of the Institute of Mediterranean Studies geophysical survey covered almost all of the remaining fenced archaeological site and parts of the surrounding area -a total surface of 48,600 sq.m.
Geophysical prospections involved both resistivity and magnetometry, as well as the use of ground penetrating radar.
In addition, all the visible and excavated remains of the ancient agora were mapped with high accuracy GPS and total stations. North of the palaestra, the northern (back) side of the portico which surrounded the temple (area C -the sanctuary was identified in 2004) seems to have had alternated semi-circular and rectangular apses, a feature encountered in many stoas of the Hellenistic and Roman world.
In addition, architectural remains were discovered exactly north of the peristyle. Most impressive are the structures detected to the south of the bouleuterion and the long stoa (area D). Here, we seem to have at least one street and parts of city blocks, thus proving that the stoa and the bouleuterion defined the agora towards the south.
Of equal interest are the features recognized in the area directly north of the theater (area E), including a large rectangular peristyle, some 12 by 15 m, and to the east of it part of a street oriented N-S.
Another street with the same direction and a width of 5 m can be seen to the west of the museum. A very long stretch of the modern asphalt road leading from the village to the archaeological site was investigated with ground penetrating radar.
The road seems to have overlaid a number of structures. If these structures are ancient, this would mean that the central road of early modern and modern Vasiliko does not represent an ancient artery. If it does, then we must assume that at some point during the long term history of the region, the ancient road was abandoned and built over. Further research will help us to solve the problem.