The magnitude 4.3 shock on August 4, 2026, recorded southwest of Pisa – with a second shock of magnitude around 3.2 at 13:05 –, has brought attention back to seismicity in Tuscany. A territory that, although not among the most dangerous in Italy, presents active faults, high-risk areas, and a complex seismic history, documented by the main national archives.
Active faults in Tuscany
According to the INGV (National Institute of Geophysics and Volcanology, editor’s note), seismicity in Tuscany is governed by two major fault systems:
- The faults of the northern Apennines
Extensional structures crossing Garfagnana, Lunigiana, Mugello, Val Tiberina. They are responsible for the strongest earthquakes in the regional history. The area is classified as having high seismic hazard by the national map.
- The transverse faults of the Apuan Alps
Connected to the earthquakes of Lunigiana and the Massa-Carrara area. Experts describe them as “structures running along the northern edge of the Apuan Alps,” capable of generating even significant events.
- The coastal faults between Pisa and Livorno
Active faults located under the sea, in front of the Pisa and Livorno coasts. According to INGV, these could have generated the shock of August 4, 2026. The area is characterized by predominantly coastal seismicity, with events distributed along the Pisa-Livorno strip.
Seismic risk areas in Tuscany
Tuscany presents very variable hazard. The most exposed areas, according to INGV and the Tuscany Region, are:
High-risk areas
- Garfagnana and Lunigiana
– Epicenter of the devastating earthquake on September 7, 1920 (Magnitude 6.5).
– Historically the most dangerous area of the entire northern Apennines.
- Massa-Carrara / Fosdinovo
– Area classified as high hazard by MPS04.
– Hit by significant events in 1767 (Magnitude 5.3), 1887 (M 5.9), 1995 (M 5.0), and 2013 (M 5.1).
Medium-risk areas
- Mugello
– Historically active, with destructive earthquakes in 1919 (Magnitude 6.4).
– Classified as medium-high hazard.
- Val di Cecina – Castelnuovo Val di Cecina
– Area with frequent instrumental seismicity (The last magnitude 3.0 earthquake on April 6, 2026).
Read more Earthquake in Tuscany, readers’ testimonies: «A roar and then the house shook»
Moderate-risk areas
- Pisa – Livorno – Western coast
Medium seismic hazard, according to INGV. In the past, no strong earthquakes are recorded in the immediate Pisa area, except for the historic Orciano Pisano earthquake of 1846 (Magnitude 6.0).
How long has it been since such a strong earthquake was recorded in Tuscany?
To answer, it is necessary to cross INGV and Tuscany Region data. The last magnitude 4 earthquake in Tuscany before August 4, 2026, was on March 26, 2026 with epicenter in Pistoia (Magnitude 4.1). Epicenter 7 km north of the city. It is also the only event of magnitude equal to or greater than 4 recorded in Tuscany in 2026 before the Pisa shock.
In the province of Pisa
INGV confirms that no earthquakes equal to or greater than magnitude 4 have been recorded in the province of Pisa from 1985 to today, before August 4, 2026. The event of August 4, 2026 (ML 4.3) is therefore the strongest recorded in the Pisa area in modern times.
Below are the strong events in the region in recent decades:
- 2013 – Lunigiana (Magnitude 5.1)
- 1995 – Fosdinovo (Magnitude 5.0)
- 1920 – Garfagnana (Magnitude 6.5)
- 1846 – Orciano Pisano (Magnitude 6.0)
The shock of August 4, 2026, is therefore the strongest earthquake recorded in Tuscany in 2026 and the most intense in the province of Pisa in over a century and a half.
Why was the August 4 shock felt so far away?
According to experts, the earthquake of August 4, 2026 was felt as far as Florence, La Spezia, Genoa, and Bologna because:
- the magnitude is “quite significant”;
- the depth (8 km) favored the propagation of the waves;
- the geological structure of the coastal area amplifies the transmission of the signal.
A complex region
Tuscany is not among the most seismic regions of Italy, but it presents active faults, high-risk areas, and a significant seismic history. The shock of August 4, 2026 reminds us that even areas with “medium” hazard, such as the Pisa coast, can generate relevant events. Prevention – as demonstrated by the post-1995 interventions in Lunigiana – remains the key to reducing damage and increasing the resilience of the territory.
