At 12:47 on June 30, 2025, a magnitude 4.6 earthquake occurred in the area of the Phlegraean Fields (Campi Flegrei) near Naples. The rare event is considered the most violent in this volcanically active area for over four decades and caused noticeable panic in the surrounding villages.
Shortly after the quake on March 13, a quake of the same magnitude had already been registered in the region. Today's earthquake was also located at a shallow depth of around five kilometers, with its epicenter near Bacoli, Monte di Procida and Pozzuoli. Numerous residents reported a "long, strong tremor" that was felt throughout the greater Naples area.
The consequences for the population were initially noticeable: people flocked to the streets in panic. However, the authorities initially gave the all-clear, as no injuries or significant damage were reported. The mayor of Pozzuoli, Luigi Manzoni, explained that emergency services and volunteers were monitoring the situation and that high-risk areas were temporarily cordoned off and secured as a precautionary measure.
A description by the mayor of Bacoli, Josi della Ragione, caused concern: a coastal cliff in the Isolotto Pennata area had loosened as a result of the quake and slipped. In some cases, buildings were evacuated, including offices in the administrative center and kindergartens, while the emergency services were working on site.
Geological background and current developments
The Campi Flegrei are a huge volcanic caldera, often referred to as the Supervolcano west of Naples, which is characterized by centuries of bradysimic soil uplift. In the second half of the 20th century, considerable uplift occurred. Since the early 1970s, there have been phases of ground uplift and repeated, often smaller earthquakes. In recent years, however, seismic activity has increased noticeably.
Today's quake is one in a series of stronger events. A magnitude 4.6 quake was already recorded in March 2025. Similar events occurred in 2024 and 2023, although the magnitudes were usually slightly lower. Geological research has been warning of the increasing tension under the caldera for years, but without being able to predict short-term eruption scenarios.
Situation of the authorities and further measures
The National Institute of Geophysics and Volcanology (INGV) and the civil protection authorities are in close contact and are continuously monitoring the situation. The mayor of Pozzuoli announced that emergency zones have been set up and protected areas, such as schoolyards and public squares, have been prepared. Citizens have been asked to stay at a safe distance from buildings or cliff faces and to monitor official information channels.
Following the main shock event, an aftershock of magnitude 2.2 occurred at 12:51, which was also recorded at a depth of around 4 kilometers. Although there was no damage, this aftershock confirms the importance of closely monitoring seismic activity.
