Hekla: A Deep Dive into Iceland's Gateway to Hell
For centuries, Europeans believed that the gates of Hell stood open atop a brooding mountain in southern Iceland. That mountain was Hekla, one of the most active volcanoes in the country and the source of some of its most violent eruptions. Reaching about 1,491 metres, Hekla is a distinctive elongated ridge rather than a simple cone, and its long history of sudden, ash-laden eruptions made it a figure of dread in the medieval imagination and a subject of intense study today.
A volcano shaped like a boat
Unlike the classic conical stratovolcano, Hekla has an unusual elongated form, built along a fissure rather than around a single central vent. Icelanders sometimes describe its profile as resembling an overturned boat. This shape reflects its origin on a volcanic ridge in the active rift zone of southern Iceland, where the splitting of the crust along the Mid-Atlantic Ridge feeds a line of vents rather than a single point.
The medieval gateway to Hell
Hekla's reputation in medieval Europe was fearsome. After a major eruption in 1104, which spread ash across much of Iceland, the volcano became firmly associated with the underworld in the European imagination. Writers described it as a prison for damned souls, and the belief that Hekla was an entrance to Hell persisted for centuries. The connection of volcanic fire, smoke, and roaring with notions of the infernal was a natural one in the medieval mind.
A long and varied eruptive history
Hekla has erupted many times since Iceland was settled, including significant events in 1104, 1300, 1693, 1766, 1845, 1947, 1970, 1980, 1991, and 2000. Its eruptions vary widely in style and size, from explosive ash-producing outbursts to lava-effusing episodes. A characteristic feature is that the longer Hekla remains dormant between eruptions, the larger and more explosive the next eruption tends to be — a pattern that shapes how scientists assess its current risk.
The 1947 and 1970 eruptions
The 1947 eruption was one of Hekla's largest in modern times, beginning with a powerful explosive phase that sent an eruption column soaring tens of kilometres high and showering ash over a wide area, before settling into a lava-producing phase that lasted over a year. The 1970 eruption, by contrast, was notable for spreading fluorine-rich ash that poisoned grazing land and killed livestock, illustrating a less obvious but serious volcanic hazard.
Fast onset and the monitoring challenge
One of Hekla's most dangerous traits is how little warning it gives. Some eruptions have begun with only a short period of detectable seismic activity before magma reaches the surface, sometimes under an hour. This rapid onset poses a serious challenge, especially as Hekla has become a popular hiking destination. Iceland's Meteorological Office monitors the volcano closely, ready to issue warnings on very short notice.
Hekla and the Icelandic landscape
The eruptions of Hekla have profoundly shaped the surrounding region, blanketing it in tephra and lava and creating the stark, dramatic landscapes typical of Iceland's volcanic interior. Layers of Hekla ash, distinctive and widely dispersed, serve as important time markers for geologists and archaeologists across Iceland and beyond, helping to date events in the island's history.
Climbing the gateway
Today Hekla can be climbed when conditions allow, offering hikers a route across fresh lava fields and ash slopes to a summit ridge with sweeping views over southern Iceland. The ascent is a powerful experience precisely because of the volcano's reputation and its capacity to erupt with little warning — a reminder that the ground underfoot is among the most restless in Europe.
Explore on the map
Hekla stands among Iceland's great active volcanoes, from Katla and Eyjafjallajokull to the Bardarbunga system in the highlands. Explore it on the interactive map — filter by country to see Hekla alongside Iceland's other volcanoes and to trace the volcanic rift that splits the island in two.