On Italy's island of Sicily, Mount Etna has spewed lava almost continuously for thousands of years, threatening inhabitants, but also supporting flora and fauna.
Italy's Mount Etna lays claim to several titles. It is:
Mount Etna rises 3,357 meters (11,014 feet) above Catania, a city on the east coast of Sicily, Italy.
It covers an area of 1,250 square kilometers (482 square miles).
Mount Etna is what geologists and volcanologists call astratovolcanoorcomposite volcano.
Stratovolcanoes typically have steep inclines and many separate vents, formed over tens to hundreds of thousands of years.
According to Italy's National Institute of Geophysics and Volcanology (INGV),Etna has more than 500,000 years of eruptive history, but it's only taken its current, conical shape in the past hundred thousand years.
Stratovolcanoes can be highly explosive when they erupt. They spew a variety of magma types, including basalt, andesite, dacite, and rhyolite.
When UNESCO inscribed Mount Etna as a World Heritage Site in 2013, it said it was "an iconic site" that continued "to influence volcanology, geophysics and other Earth science disciplines. The volcano also supports important terrestrial ecosystems including endemic flora and fauna, and its activity makes it a natural laboratory for the study of ecological and biological processes."
It is difficult to determine the exact level of danger posed by Mount Etna. When it began erupting in June 2025, INGV set its alert level for Etna as "basic."
While the volcano has beenspewing lava non-stop for thousands of years, volcanologists can pinpoint new eruptions at least once or twice a year.
According to the INGV, Mount Etna is in a state of persistent activity, with "continuous outgassing [which] can evolve into low energy Strombolian activity."
"Strombolian" describes a type of eruption, caused by expanding gas that ejects clots of glowing lava in a cycle of almost continuous, small eruptions.
Etna is also prone to "terminal and sub-terminal eruptions" at craters at the top of the volcano or nearby, and "lateral and eccentric eruptions" at vents along the slopes of the volcano.
Few people live within 5-10km (3.1-6.2 miles) of Mount Etna, but they do face a constant threat of debris and dust, even from the smallest eruptions.
Lava flows have been known to reach as far as the eastern seaboard of Sicily and run off into the Ionian Sea.
It is about 40km from Etna to Catania, which has a population of more than 300,000 people, mostly in its outskirts.
Research by the GEOMAR Helmholtz Centre for Ocean Research in Kiel, Germany, suggested the eastern flank of Mount Etna was "slowly sliding towards the sea."
In 2021, researchers at the Helmholtz Centre for Geosciences saidthe flank was sliding into the Ionian Seaat a rate of centimeters per year: "Such unstable flanks could fail catastrophically, triggering landslides that could generate tsunamis."
This has happened in the past, about 8,000 years ago.
Mount Etna and its surroundings are home to avariety of animals, including foxes, wild cats, porcupines, pine martens, rabbits, hares; and birds of prey like sparrowhawks, buzzards, kestrels, peregrine falcons and golden eagles.
Farming has left a significant human footprint around Mount Etna, largely because volcanic soil is good for agriculture.
As the British Geological Survey explains, "Volcanic deposits are rich with magnesium and potassium […] when the volcanic rock and ash weathers, the [magnesium and potassium] are released, producing extremely fertile soils."
The volcano has also shaped its surrounding woodlands: vineyards, olive groves, orchards, hazelnut and pistachio groves flourish, and higher up, birch trees are exclusive to the area.