Europe has active volcanoes, mostly in Italy and Greece. There are also volcanic fields that could erupt again someday in Germany, France, and Spain, and other European volcanoes are located on islands that are considered part of Europe.
Active volcanoes are most often defined as any that have erupted in the past 10,000 years. It’s highly possible, however, for volcanoes that have gone longer than 10,000 years to erupt again.
Greece has four active volcanoes, including the Santorini Volcano, responsible for the third-largest volcanic eruption of the past six thousand years. The four volcanoes form an arc across the Aegean Sea, and it is called the South Aegean Volcanic Arc, as shown above.
Note: For those unfamiliar with basic volcanology terms, see Types of Volcanoes and Volcanology Terms.
Greece volcano #1 - Methana
The Methana Peninsula, part of the mainland of Greece.
Located on a small peninsula 30 miles (50 km) from the capital city of Athens, the volcanic field located here has a total of 32 volcanoes, many of which had been active until all activity halted after an eruption in 1700. Other than some volcanoes in Italy, such as Mount Vesuvius, the Methana Peninsula is the only other place in mainland Europe with a volcano that has erupted in the past 10,000 years.
These volcanoes are mostly lava domes, although the most recent eruption came from an underwater volcano just north of the peninsula. One of the lava domes erupted spectacularly in 230 BC, and it was written about by famous ancient Greek writers, who also described hot springs existing on the peninsula afterward.
Greece volcano #2 - Milos
White volcanic tephra visible at Sarakiniko Beach, on the island of Milos.
The Aegean Sea exists between Greece and Turkey, and has many islands, nearly all of which are part of Greece. This includes many that are very close to mainland Turkey.
Milos is an island in the Aegean Sea. Most of the islands in this sea are not volcanic, although a few are. Major eruptions at this location took place 90,000 years ago, and the most recent known eruption, which was on a much lesser scale, occurred in about 140 AD. At the present time heat from the volcano fuels sulfurous hot springs.
The island has been inhabited for thousands of years, and today has a few thousand residents. It is famous for beautiful beaches, amazing statues, and some ancient ruins that include an amphitheater. The island is 14 miles (23 km) in diameter.
Greece volcano #3 - Nisyros
Volcanic crater on the island of Nisyros, Greece.
An island located just 10.5 miles (17 km) from mainland Turkey, in the Aegean Sea, this volcano erupted three times in the late 1800s. It continues to emit volcanic gasses.
Nisyros is five miles (eight km) across and roughly circular in shape, and features a caldera that is 2.1 miles (3.5 km) wide. It is a tourist destination, although visited less than many other Greek islands in the Aegean Sea.
Greece volcano #4 - Santorini
Santorini Island, a massive volcano, as seen from space.
The most active portion of the South Aegean Volcanic Arc is Santorini Caldera, which consists of multiple shield volcanoes and calderas overlapping one another. The island of Santorini, also called Thera, is an extremely popular tourist destination and has over 15,000 residents.
An earthquake registering 7.8 on the Richter scale did a lot of damage in 1956. The most recent volcanic eruption, from the center of a lagoon bounded by Santorini and a few smaller islands, occurred in 1950.
In about 1,600 BC there was an eruption registering level seven on the Volcanic Explosivity Index (with level eight being a supervolcanic eruption), which expelled an estimated 100 cubic kilometers of material. This eruption was so large that only two are known to have been larger in the past six thousand years. Mount St. Helens in Washington, by comparison, ejected one cubic km of material in its famous large eruption of 1980, registering level five on the VEI.
As another comparison, the famous 1883 eruption of Indonesia’s Krakatoa, which was heard 3,000 miles (4,800 km) away, destroyed or damaged 300 cities and towns, and killed over 36,000 people, ejected 21 cubic kilometers of material, just 21% the quantity of Santorini’s massive eruption, registering level six on the VEI.
There are at least ten eruptions of Santorini known since the massive one that occurred 3,600 years ago, although none have been comparable in size.
The Santorini Eruption of 1,600 BC heavily damaged the ancient Minoan civilization that existed on the island of Crete to the south. A settlement on Santorini was completely destroyed. It appears to have also damaged the coast of Crete, probably by way of tsunami.