How Many Volcanoes Are in Iceland? (2026 Data)

Iceland has had 12¹ volcanic eruptions in the 2020s alone, more than in any full decade since 1900. About one third² of the island, roughly 11,600 square miles (30,000 km²), lies within its active volcanic zones, and the Icelandic Met Office's seismic network records about 87³ reviewed earthquakes on an average day. Counting the volcanoes behind all this is harder than it sounds, because scientists count volcanic systems, not single mountains, and the most repeated number online has no official source at all.

The stakes are real. The Laki eruption of 1783–84 was followed by famine that killed about 9,500¹ people, around 19%⁴ of Iceland's population, and the 2010 eruption of Eyjafjallajökull forced the cancellation of 104,000⁵ flights across Europe in eight days. This report brings together the official Catalogue of Icelandic Volcanoes, peer-reviewed research, the Met Office's earthquake catalogue and EUROCONTROL's figures to show how many volcanoes Iceland has, how often they erupt and which are the biggest.

Iceland's volcanoes, counted

The official answer comes from the Catalogue of Icelandic Volcanoes, run by the Icelandic Met Office, the University of Iceland and Iceland's Civil Protection. It lists 33¹ volcanic systems. A volcanic system is not one mountain: it is a zone of fissures and craters, often around a central volcano, fed by the same magma, and the longest, Askja and Bárðarbunga, each stretch about 118 miles¹ (190 km). Fremrinámar and Kverkfjöll run about 81 miles¹ (130 km), Grímsvötn and Krafla about 62 miles¹ (100 km), and even the Reykjanes system is about 28 miles¹ (45 km) long.

Other sources count differently. The European research infrastructure EPOS refers to 32⁶ volcanic systems in Iceland's active volcanic zones, and a peer-reviewed review of Iceland's volcanism since the last ice age attributes most of it to 30⁷ active systems in the volcanic zones. Counting systems under the sea as well, an overview on natt.is puts the total at around 41⁸. A figure of about 130 volcanoes is widely repeated online, but no primary source for it could be found, so it is not used here.

Number of active volcanic systems in Iceland

Not all of the systems are equally alive. The Catalogue rates 5¹ as highly active: Bárðarbunga, Grímsvötn, Hekla, Katla and Fagradalsfjall. 12¹ are rated moderate and 14¹ low. Only 2¹, Snæfell and Tindfjallajökull, are marked inactive, which leaves 31¹ systems that are not.

How many active volcanoes are in Iceland

Five systems do most of the work. Over the last 1,100 years, Grímsvötn has erupted about once every 10 years¹, and Bárðarbunga and Katla about once every 50 years¹ each. Others are far slower: the Catalogue puts Öræfajökull at about one eruption every 500 years¹ and Esjufjöll at about one every 1,000 years¹. The fifth, Fagradalsfjall, lies on the Reykjanes Peninsula.

Many of Iceland's volcanoes sit under ice. The Catalogue describes glacier or ice cover on part of 16¹ of the 33 systems, including Grímsvötn and Katla, both under ice up to 2,300 feet¹ (700 m) thick; Katla's ice-filled caldera measures about 5.6 by 8.7 miles¹ (9 by 14 km). "The most active volcanoes in the country are covered or capped by a thick glacier," the 2008 review notes.⁷ Katla's eruption of 1823 was followed by a flood in which 3¹ people drowned.

Number of active volcanoes in Italy vs Iceland

International comparisons usually count individual volcanoes rather than systems, and the result depends on the list. The volcano list of NOAA's National Centers for Environmental Information, based on older data from the Smithsonian Institution's Global Volcanism Program, includes 44¹⁰ volcano locations in Iceland, against 15¹⁰ in Italy and 113¹⁰ in Japan. The United States tops that list with 191¹⁰, followed by Russia with 170¹⁰ and Indonesia with 136¹⁰.

How often do volcanoes erupt in Iceland

Over the long run, Iceland averages at least 20⁷ eruptions per century, according to the 2008 peer-reviewed review of its volcanism. Since the end of the last ice age, about 11,000 years ago, Icelandic volcanoes have produced around 2,400⁷ eruptions and about 566 km³⁷ of magma, roughly 136 cubic miles. In historical time, roughly the last 1,100 years, the count is 217⁷: 161⁷ explosive and 56⁷ effusive. Three in four eruptions are explosive, and about 86%⁷ of those are "wet".

Grímsvötn is the most active system by far, with about 110¹ eruptions in the last 1,100 years. Bárðarbunga follows with at least 26¹, Hekla with 23¹ in the last millennium and Katla with at least 21¹. The small Eldey system has had 6¹ small submarine or explosive eruptions over the same period.

How many eruptions in Iceland since 1900?

Counting the Catalogue's records and the recent Reykjanes eruptions, Iceland has had 48¹ confirmed eruptions since 1900, about one every 2.6 years¹¹ on average. They come in bursts rather than evenly. The 1980s brought 8¹, mostly small fissure eruptions at Krafla between 1975 and 1984, while the 1950s had 0¹. The 2020s, not yet over, already hold the record with 12¹.

A straight line through the counts per decade rises by about 0.4¹¹ eruptions a decade and points to roughly 7¹¹ per decade by the 2040s. That trend is illustrative only: eruptions arrive in episodes such as the Krafla eruptions and the Reykjanes series, and the peer-reviewed long-term average of at least 20⁷ per century is the steadier guide.

Eruptions have started in every month of the year. Of the 40¹ eruptions since 1900 with a known start month, March has the most, 6¹, and June the fewest, 1¹. With so few events, the pattern does not point to a volcanic season.

All of the 2020s eruptions happened on the Reykjanes Peninsula, where the previous eruption had been around 1240.¹ Fagradalsfjall erupted in 2021, 2022 and 2023, and from December 2023 the Sundhnúkur crater row produced 9¹ eruptions by August 2025. The first Fagradalsfjall eruption, in Geldingadalir, lasted about 183 days⁹, while the eighth Sundhnúkur eruption in April 2025 lasted about 1 day⁹. According to the Catalogue, the 2021 eruption covered 4.85 km²¹ (about 1.9 square miles) with 0.15 km³¹ of lava, and the 2022 eruption added 0.01 km³¹ over about three weeks. The first three Sundhnúkur eruptions each ended within 3 days⁹, while the fourth, from March to May 2024, went on for 53 days⁹. The dates come from a compiled eruption timeline (volcanoexpress.is); the Met Office confirmed that the ninth eruption had ended on 5 August 2025.¹² As of September 2026, the Met Office's aviation colour code for the Reykjanes volcano is yellow, which signals elevated unrest.¹³

Some famous volcanoes have been quiet for a long time. Katla last erupted in 1918¹, 108 years¹¹ ago. Hekla last erupted in 2000¹, and Öræfajökull, the tallest volcano in the country, in 1727¹, 299 years¹¹ ago.

Biggest volcanoes in Iceland

Measured by height, the biggest is Öræfajökull, whose summit reaches 6,923 feet¹ (2,110 m). Bárðarbunga follows at 6,562 feet¹ (2,000 m) and Kverkfjöll at 6,342 feet¹ (1,933 m). Better-known names are lower: Eyjafjallajökull rises to 5,417 feet¹ (1,651 m), and Hekla and Katla to 4,888 feet¹ (1,490 m) each. The lowest system in the Catalogue, Eldey, reaches just 230 feet¹ (70 m).

Biggest volcanic eruption in Iceland

By volume of lava, the largest eruption since the last ice age produced the Þjórsá lava about 8,600 years ago: 25 km³⁷, about 6.0 cubic miles. In historical time, the record belongs to Eldgjá, which erupted between 934 and 940 and poured out 19.6 km³⁷ (4.7 cubic miles). Laki, in 1783–84, followed with 15.1 km³⁷ (3.6 cubic miles).

Laki was also the deadliest. The Catalogue records about 9,500¹ deaths from famine and disease after the loss of more than 200,000¹ farm animals, around 19%⁴ of Iceland's population at the time. Statistics Iceland's records show the population falling from 49,753⁴ at the start of 1784 to 40,381⁴ at the start of 1786, a drop of 9,372¹¹ people in two years. Hekla's eruption of 1300 was followed by a famine that killed about 600¹ people. The most recent death in the Catalogue's eruption records came in 1947, when a scientist filming Hekla's eruption was killed by a glowing block.¹

The largest lava eruption of this century so far was Holuhraun, on the Bárðarbunga system, which ran from August 2014 to February 2015 and produced 1.6 km³¹ of lava.

Volcanoes are only half of the story underground.

Earthquakes in Iceland

How many earthquakes in Iceland per day

The Icelandic Met Office's network detects thousands of small earthquakes every year. Counting the reviewed events in its catalogue for Iceland and the surrounding shelf, the average from 2016 to 2025 was 31,721³ a year, or about 87³ a day. Including events detected only automatically, the average rises to about 117³ a day.

Busy years follow unrest. The most reviewed earthquakes came in 2020, with 48,002³, and the most detections overall in 2021, the year Fagradalsfjall began to erupt, with 72,651³. In 2014, the year of the Holuhraun eruption, 45,634³ earthquakes were reviewed, while the quietest year since 2000 was 2006, with 9,301³. Single months can be extreme: the Met Office's monthly overview reports nearly 10,000¹⁴ earthquakes in January 2024, against just over 1,750¹⁴ in December 2024. Counts from the early 1990s are not comparable: the network was less sensitive and recorded only about 2,400³ earthquakes a year. The chart below therefore fits its trend to 2000–2025 only, and the wide range shows how much single years swing.

Biggest earthquake in Iceland

The largest known earthquakes in Iceland reach about magnitude 7. The South Iceland earthquake of 14 August 1784 has been estimated at 7.1¹⁵, and earthquakes in 1910 off the north coast, in 1912 in Rangárvellir and in 1963 at the mouth of Skagafjörður at 7.0¹⁵ each. In June 2000, two earthquakes of magnitude 6.5¹⁵ struck South Iceland four days apart. On 29 May 2008, an earthquake near the mountain Ingólfsfjall, about 3 miles (5 km) northwest of Selfoss, was reported by the Met Office at 6.1¹⁶ on the day. A later study modelled it as two shocks of magnitude 5.8¹⁷ and 5.9¹⁷ and noted that teleseismic data gave a magnitude of 6.3¹⁷.

When eruptions reach the world

Most Icelandic eruptions are local events. Eyjafjallajökull in 2010 was not. Its ash cloud closed much of European airspace: EUROCONTROL counted 104,000⁵ cancelled flights between 15 and 22 April, 48%⁵ of expected traffic over those eight days, and 80%⁵ of flights were cancelled on 18 April alone. About 10 million⁵ passengers could not board their flights, and further ash in May added another 7,000⁵ cancellations. On 18 April, Europe had fewer than 5,000⁵ flights, against 24,700⁵ the Sunday before, and traffic did not return to normal until 23 April. Looking back in 2021, EUROCONTROL put the airlines' losses at €2.7 billion¹⁸ and estimated that a similar event today could cause up to 50,000¹⁸ cancellations.

How much CO2 did the Iceland volcano emit?

Iceland's largest lava eruption this century released more gas than the whole country's human activities. The Met Office's final estimate for Holuhraun is 9.6 million tonnes¹⁹ of sulphur dioxide and 5.1 million tonnes¹⁹ of carbon dioxide. Iceland's human-caused emissions in 2015 were 0.06 million tonnes¹⁹ of sulphur dioxide and 3 million tonnes¹⁹ of carbon dioxide, so the eruption released almost twice the carbon dioxide. The Met Office text calls the sulphur dioxide "16 times" the human total, but its own figures put the ratio at about 160 times¹⁹ (9.6 ÷ 0.06). The Met Office adds that Holuhraun released the most sulphur dioxide of any effusive eruption in the world on an annual basis since 1978¹⁹, along with about 0.1 million tonnes¹⁹ of hydrogen chloride. For context, Iceland's total greenhouse gas emissions in 2024, including land use, were 11.0 million tonnes²⁰ of CO₂ equivalent, of which 6.3 million tonnes²⁰ came from land use. These totals cover all greenhouse gases, so they are not directly comparable with a volcano's carbon dioxide alone. No official carbon dioxide total could be found for the 2021–2025 Reykjanes eruptions.

What the numbers mean

Iceland lives with eruptions as a regular event, not a rare disaster: 48¹ since 1900, about one every 2.6 years¹¹, and 12¹ in the 2020s so far. Most are small, but the record shows how far the effects can reach, from famine after Laki to 104,000⁵ cancelled flights in 2010 and gas emissions far above the country's own.

The Met Office's aviation colour codes run from green, for normal, through yellow and orange to red, for an eruption with significant ash. Bárðarbunga returned to green in June 2026 and Grímsvötn in January 2025, but the Reykjanes volcano has stayed yellow, signalling elevated unrest, since 5 August 2025.¹³ Ice adds another layer of risk and uncertainty, with 16¹ of the 33 systems partly under ice. The same geology also powers the country: geothermal energy provides over 60%²¹ of Iceland's primary energy.

Conclusions

1. There is more than one right answer to the question. The official Catalogue counts 33¹ volcanic systems, 31¹ of them not marked inactive, while lists of individual volcanoes or offshore systems give higher numbers, and the popular "130" has no source.
2. The 2020s are already the busiest decade for eruptions since 1900, with 12¹ so far, all of them on the Reykjanes Peninsula.
3. The most active volcanoes are often under ice: 3¹ of the 5¹ highly active systems, Bárðarbunga, Grímsvötn and Katla, are partly glacier-covered, as the peer-reviewed review also notes.
4. The biggest impacts came from lava floods and gas, not only from explosions. Laki, a lava eruption, was followed by famine and disease that killed about 9,500¹ people, and Holuhraun released 9.6 million tonnes¹⁹ of sulphur dioxide, against 0.06 million tonnes from all human activity in Iceland in 2015.