Volcanism
Ischia belongs to the volcanic system of the Phlegraean Fields, a crater where the signs are volcanism are very much present with fumaroles, the solfatara of Pozzuoli, the thermal baths of Agnano in Naples, etc.
The island also has a secondary volcanic activity, which is manifested by minor phenomena, such as solfataras (emissions of superheated steam mixed with sulphur), fumaroles and mofette (hot emissions of steam and carbon dioxide) and, especially, thermal waters, rich in beneficial substances.
The island also has a secondary volcanic activity, which is manifested by minor phenomena, such as solfataras (emissions of superheated steam mixed with sulphur), fumaroles and mofette (hot emissions of steam and carbon dioxide) and, especially, thermal waters, rich in beneficial substances.