With the aim of drawing a new geological map in scale 1:10.000, the detailed geological survey of a large area of Campi Flegrei, from Procida up to the Sebeto valley, was carried out in the last years. In this area we highlighted some geological sites that can be considered potential geosites due to rarity, scientific, educational and historical value. Particularly, we pointed out: the Breccia-Piperno Formation, cropping out in the Soccavo-Pianura area, which represents one of the most ancient products of the phlegrean history; the Solfatara, for centuries utilized as a mine, today is one of the principal monitoring center of Campi Flegrei and with its vapours testifies the phlegrean activity; the Monte di Cuma, seat of the first Greek colony in Italy and rich of Greek-Roman archaeological remains; the Averno lake, which in Roman age was an inner sea connected to Cuma by the Viadotto of Cocceio; the Monte Nuovo, a testimony of the only historical eruption of Campi Flegrei, occurred in 1538, which completely modified the geography of this area.
The authors believe that these geosites, thanks to their singular geological and historical-cultural value, satisfy all the requirements necessary to form, within the Regional Park of Campi Flegrei, the first volcanological European park: the European Geopark of Campi Flegrei.
The connection between the geosites is guaranteed by present roads and, where possible, by Roman tunnels caved in ancient times for military aims.