Sixteen eruptions have been recorded for Katla since 930.
The last major eruption started on 12 October 1918 and lasted for 24 days.
It was likely a VEI-5 level eruption.
The 1918 eruption resulted in extending the southern coast by 5 km due to laharic flood deposits.
Its present dormancy is among the longest in known history.

Minor (VEI-1?)
eruptions occurred in:
2011 – VEI-1
1999 – VEI-1
1955 – VEI-1
Major eruptions occurred in:
1918 – VEI-4
1860 – VEI-4
1823 – VEI-3
1755 – VEI-5;
1721 – VEI-5
1660 – VEI-4
1625 – VEI-5
1612 – VEI-4
1580 – VEI-4
934 – VEI-5 or VEI-6, 5 cubic km of tephra and 18 cubic km of lava
Most of these eruptions resulted in glacial floods.
The severe fissure eruption in 934 was one of the largest lava eruptions in the past 10,000 years.
Before the Hringvegur (Iceland's Ring Road) was constructed in 1974, people feared traversing the plains in front of the volcano because of the frequent jökulhlaup (or glacier bursts) and the deep river crossings.
Especially dangerous was the glacier outburst that followed the eruption of 1918.
Sixteen eruptions have been recorded for Katla since 930. The last major eruption started on 12 October 1918 and lasted for 24 days. It was likely a VEI-5 level eruption. The 1918 eruption resulted in extending the southern coast by 5 km due to laharic flood deposits. Its present dormancy is among the longest in known history.
Minor (VEI-1?) eruptions occurred in:
2011 – VEI-1
1999 – VEI-1
1955 – VEI-1
Major eruptions occurred in:
1918 – VEI-4
1860 – VEI-4
1823 – VEI-3
1755 – VEI-5;
1721 – VEI-5
1660 – VEI-4
1625 – VEI-5
1612 – VEI-4
1580 – VEI-4
934 – VEI-5 or VEI-6, 5 cubic km of tephra and 18 cubic km of lava
Most of these eruptions resulted in glacial floods. The severe fissure eruption in 934 was one of the largest lava eruptions in the past 10,000 years. Before the Hringvegur (Iceland's Ring Road) was constructed in 1974, people feared traversing the plains in front of the volcano because of the frequent jökulhlaup (or glacier bursts) and the deep river crossings. Especially dangerous was the glacier outburst that followed the eruption of 1918.
Katla (volcano)