# Campi Flegrei: the ground rises and falls

> Pozzuoli rose by up to 3.5 meters in two 20th-century crises and has been rising again since 2005. What bradyseism is, and where the current number is.

URL: https://myitalia.it/stories/the-ground-that-breathes
Last updated: 2026-09-02

The ground at Pozzuoli rose by up to around 3.5 meters during the bradyseismic crises of 1970 to 1972 and 1982 to 1984, and it has been rising steadily again since 2005.

## Up to 3.5 meters, twice, in living memory

Bradyseism is the slow vertical movement of the ground, and at Pozzuoli it reached up to around 3.5 meters across the 2 crises of the 20th century.

Two crises did most of the recorded work: 1970 to 1972, then 1982 to 1984. Together they lifted Pozzuoli by up to around 3.5 meters. Harbor steps, doorways and quaysides in the town record it directly, because the sea moved away from them.

A new uplift has been under way since 2005, and the Civil Protection Department puts the caldera's rise since then at over 150 cm.

## A caldera 110,000 years old, quiet since 1538

The Campi Flegrei have been an active caldera for more than 110,000 years, and the last eruption was in 1538, when Monte Nuovo was formed.

More than 27 eruptions are counted in the last 5,500 years. That is the timescale the monitoring is built on, and it is the reason a moving ground surface is treated as normal behavior for this system rather than as an event.

Ground deformation is not an automatic precursor of an eruption. It is the thing the instruments watch, which is a different statement.

## Yellow is the second of 4 levels

The alert level is yellow with the operational phase set to attention, fixed by a decree of October 30, 2025 and confirmed by the Civil Protection Department on November 4, 2025 after the volcanic section of the Commissione Grandi Rischi met.

The 4 levels run base, attention, pre-alarm, alarm. Yellow means a medium disequilibrium of the volcano and sits at the second step. It has been in force since 2012 and was redefined in 2025 within an update agreed with INGV and the Campania Region.

What phase 2 requires is administrative: reinforced monitoring, verification of civil protection measures, and non-structural prevention through training, information and exercises. None of those is a signal about the next month.

## The zones are planning maps, not forecasts

The national plan puts around 500,000 residents inside the red zone, the area of preventive evacuation, and over 800,000 inside the yellow zone exposed to ash fall.

The red zone takes in Pozzuoli, Bacoli, Monte di Procida and Quarto in full, part of Giugliano in Campania and Marano di Napoli, and several Naples districts including Soccavo, Pianura, Bagnoli and Fuorigrotta. The yellow zone adds Villaricca, Calvizzano, Mugnano di Napoli, Melito di Napoli and Casavatore, plus 24 Naples districts.

Those boundaries describe a civil protection scenario. They are drawn so that an evacuation could be organized, and they say nothing about probability. Reading a zone map as a risk map is the single most common mistake made with this material.

## Where the current number lives

Monitoring is run by INGV Osservatorio Vesuviano, which publishes 4 kinds of product: a monthly surveillance bulletin, a weekly bulletin dedicated to Campi Flegrei, web bulletins, and VONA notices for aviation, all at ov.ingv.it.

That is the correct way to check this subject: the current INGV bulletin for the measurements, and the Civil Protection Department for the alert level. Any page, this one included, is a snapshot of the day it was written.

Pozzuoli and Bacoli are ordinary places to visit under a yellow alert, and have been since the level was set in 2012. Ask locally about access to individual sites, which changes for reasons of maintenance and safety that have nothing to do with the alert level, and take the bulletin rather than the news cycle as your reference.

One last note on language, because it decides how the whole subject reads. An uplift of 150 cm since 2005 is a measurement. Yellow is an administrative state with 3 defined duties attached to it. Around 500,000 residents in the red zone is a planning figure. None of the three is a prediction, and no institution in Italy publishes one for this volcano. For the region, see [Campania](/regions/campania).

## FAQ

### What is bradyseism at Campi Flegrei?

The slow vertical movement of the ground inside the caldera, up and down. Two 20th-century crises, in 1970 to 1972 and 1982 to 1984, raised Pozzuoli by up to around 3.5 meters in total. A steady uplift has been under way again since 2005.

### What alert level are the Campi Flegrei at?

Yellow, the second of 4 levels, with the operational phase set to attention. It was fixed by a decree of October 30, 2025 and confirmed by the Civil Protection Department on November 4, 2025. Yellow means a medium disequilibrium of the volcano, not an imminent eruption.

### When did Campi Flegrei last erupt?

In 1538, when the Monte Nuovo cone was formed. The caldera has been active for more than 110,000 years and more than 27 eruptions are counted in the last 5,500 years.

### How many people live in the Campi Flegrei red zone?

The national plan puts around 500,000 residents in the red zone, the area of preventive evacuation: Pozzuoli, Bacoli, Monte di Procida and Quarto entirely, parts of Giugliano in Campania and Marano di Napoli, and several Naples districts. The yellow ash-fall zone holds over 800,000.

### Where can I check the current situation at Campi Flegrei?

At the INGV Osservatorio Vesuviano, which publishes 4 products: a monthly surveillance bulletin, a weekly Campi Flegrei bulletin, web bulletins and VONA notices for aviation, all at ov.ingv.it. The alert level itself is set separately by the Civil Protection Department.

## Sources

| Fact | Source | Confidence | Valid until |
|---|---|---|---|
| I Campi Flegrei sono una caldera attiva da oltre 110.000 anni, la cui ultima eruzione risale al 1538 (Monte Nuovo); il bradisismo ha prodotto crisi di sollevamento nel 1970-1972 e nel 1982-1984, con fino a circa 3,5 metri di sollevamento a Pozzuoli, e un nuovo sollevamento costante in corso dal 2005. | [INGV - Osservatorio Vesuviano](https://www.ov.ingv.it/index.php/monitoraggio-sismico-e-vulcanico/campi-flegrei); [Dipartimento della Protezione Civile](https://rischi.protezionecivile.gov.it/it/vulcanico/vulcani-italia/campi-flegrei/) | high | 2028-12-31 |
| I Campi Flegrei sono in livello di allerta GIALLO con fase operativa di attenzione: il livello e' stato stabilito con decreto del 30 ottobre 2025 e confermato dal Dipartimento della Protezione Civile il 4 novembre 2025 dopo la riunione della Commissione Grandi Rischi - settore vulcanico. | [Dipartimento della Protezione Civile](https://rischi.protezionecivile.gov.it/it/vulcanico/vulcani-italia/campi-flegrei/); [doc 2](https://www.protezionecivile.gov.it/it/comunicato-stampa/campi-flegrei-confermata-allerta-gialla-rischio-vulcanico/) | medium | 2027-03-31 |
| Il piano nazionale per i Campi Flegrei individua una zona rossa (evacuazione preventiva) con circa 500.000 residenti - Pozzuoli, Bacoli, Monte di Procida, Quarto per intero, parte di Giugliano in Campania e Marano di Napoli e diversi quartieri di Napoli - e una zona gialla esposta alla ricaduta di cenere con oltre 800.000 residenti. | [Dipartimento della Protezione Civile](https://rischi.protezionecivile.gov.it/it/vulcanico/vulcani-italia/campi-flegrei/) | medium | 2027-12-31 |
| Il monitoraggio dei Campi Flegrei e' affidato all'INGV - Osservatorio Vesuviano, che pubblica bollettini di sorveglianza mensili, bollettini settimanali dedicati ai Campi Flegrei, bollettini web e comunicazioni VONA per l'aviazione. | [INGV - Osservatorio Vesuviano](https://www.ov.ingv.it/index.php/monitoraggio-sismico-e-vulcanico/campi-flegrei) | medium | 2028-12-31 |

## Image

https://media.myitalia.it/media/region.campania.v2.1600.jpg
Author: Martuna.22. License: CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0).
Source: https://commons.wikimedia.org/wiki/File:Costiera_amalafitana_(1).jpg

## Other languages

- it: https://myitalia.it/it/storie/the-ground-that-breathes.md
- es: https://myitalia.it/es/historias/the-ground-that-breathes.md
- fr: https://myitalia.it/fr/recits/the-ground-that-breathes.md
- de: https://myitalia.it/de/geschichten/the-ground-that-breathes.md