A magnitude 4.6 earthquake struck the Campi Flegrei caldera at 12:47 PM local time on June 30. The epicenter was just off the coast of Bacoli, 16 kilometers west of Naples. It hit shallow, only 4.9 kilometers deep. That’s why it rattled so hard. This wasn’t a distant rumble. It was a jolt. People in Naples felt it. So did residents in Pozzuoli, Quarto, and Procida. Some ran into the streets. Others froze. The shaking lasted seconds, but the implications are longer.
The quake triggered a partial collapse of the Punta Pennata ridge. A chunk of the islet broke off and slid into the sea. No injuries reported. But the collapse was caught on video from a nearby boat. The footage shows the cliff face giving way and splashing down into the water. That’s not normal erosion. That’s seismic force in real time.
Campi Flegrei Activity
A Preliminary Magnitude 4.6 earthquake recently struck Campi Flegrei in Italy at a depth of 4.9km
The active Caldera near Naples has been having ongoing seismic swarms for months. Authorities are monitoring the situation#CampiFlegrei #Terremoto #Naples pic.twitter.com/zg1a0PmAOv
— Chyno News (@ChynoNews) June 30, 2025
A portion of the islet (Punta Pennata) in Bacoli collapsed into the sea after the earthquake.
A magnitude 4.6 hit 16 KM west of Napoli, Italy at 12.47 PM (Rome time) on June 30, 2025 (approximately 1 hour ago). The tremor was felt widely around Naples.#Terremoto pic.twitter.com/qzfMjSjh3e
— RenderNature (@RenderNature) June 30, 2025
This is the strongest quake in the Campi Flegrei region in 40 years. The last one of this magnitude hit in March. Before that, you’d have to go back decades. The area is under constant watch for bradyseism. That’s the slow rise and fall of the ground caused by underground magma shifts. It’s been accelerating. The ground has lifted more than 20 centimeters in the past year. That’s not theory. That’s satellite data.
Campi Flegrei is a supervolcano. It last erupted in 1538. It’s not just a crater. It’s a caldera with over 500,000 people living inside the red zone. The Italian government has updated evacuation plans. Civil protection teams are already deployed. Trains were halted. Subway lines paused. Inspections are underway on bridges and tunnels. No structural damage reported yet, but checks are ongoing.
Sources:
https://www.wantedinrome.com/news/italy-campi-flegrei-strongest-earthquake-40-years.html
https://tg.la7.it/cronaca/terremoto-campi-flegrei-video-punta-pennata-bacoli-30-06-2025-240420
https://www.agenzianova.com/en/news/fear-in-the-Phlegraean-Fields-earthquake-of-magnitude-46-a/
