A devastating earthquake occurred on 28 December 1908 in Sicily and Calabria, southern Italy, with a moment magnitude of 7.1 and a maximum Mercalli intensity of XI (Extreme). The epicentre was in the Strait of Messina which separates Sicily from the Italian mainland. The cities of Messina and Reggio Calabria were nearly destroyed and around 120,000 people died, making it the deadliest earthquake in the history of Europe.
According to Italy's National Institute of Geophysics and Vulcanology, the earthquake was caused by a large, low-angle SE-dipping, blind normal fault, lying mainly offshore in the Strait of Messina, between plates. Its upper projection intersects the Earth's surface on the western side of the Strait, Sicily's coast. In 2019 researchers at Birkbeck, University of London, discovered the active fault responsible for the earthquake. The study, led by Marco Meschis, identified the fault as the previously mapped but little-studied Messina-Taormina Fault which lies off the Sicilian coast and runs the length of the Strait of Messina. The team used data from 1907–1908 to examine the pattern of uplifts and subsidence observed in the Messina and Calabria area which bore a strong resemblance to those resulting from other powerful earthquakes triggered by normal faults. After comparing the direction and size of movements on well-known faults with the surface movements seen in Messina and Calabria, the researchers identified the probable active fault which caused the catastrophic earthquake as well as the direction and size of the movements.
Italy sits along the boundary zone of the African plate, and this plate is pushing against the sea floor underneath Europe at a rate of 25 millimetres (0.98 inches) per year. This causes vertical displacement, which can cause earthquakes. The earthquake was recorded by 110 seismographic stations around the world, and was one of the first to be recorded by instruments.
The Strait of Messina is part of the regional tectonic feature known as the Calabrian Arc, an area of differential uplift deriving from the dynamics of the Ionian and South Tyrrhenian tectonic units, two of the lithosphere blocks of microplates recognized in the highly fragmented Italian portion of the Africa-Eurasia contact. Some of the strongest earthquakes of the last centuries occurred in the Calabrian Arc, such as the 1783 and 1905 Calabrian earthquakes, as well as the more catastrophic 1908 Messina earthquake.
Records indicate that considerable seismic activity occurred in the areas around the Strait of Messina for several months prior to 28 December; it increased in intensity beginning on 1 November. On 10 December, a magnitude 4 earthquake caused damage to a few buildings in Novara di Sicilia and Montalbano Elicona, both in the Province of Messina.
A total of 293 aftershocks took place between 28 December 1908 and 11 March 1909.
In 2008, it was proposed that the concurrent tsunami was not generated by the earthquake, but rather by a large undersea landslide it had triggered. The probable source of the tsunami was off Giardini Naxos (40 km south of Messina), on the Sicilian coast, where a large submarine landslide body with a headwall scarp was visible on a bathymetric map of the Ionian seafloor. Another study attributed the source of the tsunami to having been a landslide which took place off of north-eastern Sicily and southern Calabria, most likely offshore between San Leo and Bocale in Calabria.
On Monday, 28 December 1908, at 5:20:27 an earthquake of 7.1 on the moment magnitude scale occurred. Its epicentre was in the Strait of Messina which separates the busy Sicilian port city of Messina from Reggio Calabria on the Italian mainland. Its precise epicentre has been pinpointed in the northern Ionian Sea area close to the narrowest section of the Strait, the location of Messina. It had a depth of around 9 km (5.6 mi).
The earthquake almost levelled Messina. At least 91% of the structures in Messina were destroyed or irreparably damaged and 75,000 people were killed in the city and its suburbs. Reggio Calabria and other locations in Calabria also suffered heavy damage, with some 25,000 people killed. Reggio's historic centre was almost completely eradicated. The number of casualties is based on 1901 and 1911 census data. It was the most destructive earthquake in recorded history to strike Europe. The ground shook for 37 seconds, and the damage was widespread, with destruction felt over a 4,300 km2 (1,700 sq mi) area.
In Calabria, the ground shook violently from Scilla to south of Reggio, provoking landslides inland in the Reggio area and along the sea-cliff from Scilla to Bagnara. In the Calabrian commune of Palmi on the Tyrrhenian coast, there was devastation that left 600 dead. Damage was also inflicted along the eastern Sicilian coast, but only Messina was hit as badly as Calabria. The mesoseismal area was confined near the coast along a 1-to-4-kilometre-wide (0.6 to 2.5 mi) belt that shook Messina and the surrounding villages. Catania, the largest city in eastern Sicily, did not incur notable damage.
A young doctor who escaped with his life later recounted that "the profound silence was broken by an extraordinary noise like the bursting of a thousand bombs, followed by a rushing and torrential rain." Then he heard a "sinister whistling sound" which he likened to "a thousand red hot irons hissing in the water." Other survivors reported that there were three separate and different movements during the 37-second main shock: the first shaking backwards and forwards, the second thrusting violently upwards, with the third moving in a circular motion. Most accounts concur that it was the second upwards motion that caused the widespread destruction in Messina; the accompanying noise described as having been "exactly like that made by a fast train in a tunnel".
The elevated death toll was due to the fact that most people were asleep, and killed outright or buried alive in their beds, as their houses collapsed on top of them. Thousands were trapped under debris, and died from their injuries. One week before the earthquake, 160,000 inhabitants were counted in the entire Messina commune. On 28 December, Messina was even more crowded than usual, due to the number of overnight visitors from outlying areas who had come to the city to see a performance of Giuseppe Verdi's opera Aida, which had been staged the previous evening at the Vittorio Emanuele II theatre.
About ten minutes after the earthquake, the sea on both sides of the Strait suddenly withdrew as a 12-meter (39-foot) tsunami swept in, and three waves struck nearby coasts. It struck hardest along the Calabrian coast and inundated Reggio Calabria after the sea had receded 70 metres (230 ft) from the shore. The entire Reggio seafront was destroyed and people who had gathered there perished. Nearby Villa San Giovanni was also badly hit. Along the coast between Lazzaro and Pellaro, houses and a railway bridge were washed away.
In Messina, the tsunami also caused devastation and death; many of the survivors of the earthquake had fled to the relative safety of the seafront to escape their collapsing houses. The second and third tsunami waves, coming in rapid succession and higher than the first, raced over the harbour, smashed boats docked at the pier, and broke parts of the sea wall. After engulfing the port and three city streets inland beyond the harbour, the waves swept away people, ships that had been anchored in the harbour, fishing boats and ferries, and inflicted further damage on the edifices within the zone which had remained standing after the shock.
The ships that were still attached to their moorings collided with one another but did not incur major damage. Afterwards, Messina harbour was filled with floating wreckage and the corpses of drowned people and animals. Towns and villages along the eastern coast of Sicily were assaulted by high waves which killed people and damaged boats and other property. Two hours later, the tsunami struck Malta, rushing into Marsamxett Harbour and damaging property in Msida. About 2,000 people were killed by the tsunami in Messina on the eastern coast of Sicily, and in Reggio Calabria and its coastal environs.