Lava from the Lakagígar crater row

Eldhraun was formed during a fissure eruption within the Grímsvötn volcanic system. Beginning in June 1783, activity opened along the Lakagígar crater row and continued into 1784, producing vast quantities of basaltic lava. The source landscape remains in the highlands, while Eldhraun is the broad downstream lava field created as the flows moved towards inhabited country.

The lava followed existing valleys and river channels before spreading across the lowlands around Kirkjubæjarklaustur. It altered drainage, surrounded older landforms and created a new surface on a scale that is difficult to grasp from any single viewpoint. East of Kirkjubæjarklaustur, the field continues towards Lómagnúpur, where the horizontal expanse of lava meets the mountain’s abrupt rock face.

Lakagígar and Eldhraun are therefore different parts of the same geological event. Reaching the crater row requires a seasonal journey into the highlands, but the lava that emerged there can be encountered directly beside Route 1. Eldhraun makes the distant eruption legible in the inhabited landscape it transformed.

Móðuharðindi and the cost of the eruption

The Skaftá Fires became a national catastrophe not only because of the advancing lava, but because of the gases released during the eruption. Sulphur dioxide and fluorine compounds damaged vegetation and contaminated grazing land. Livestock died in enormous numbers, food production collapsed and famine followed in communities already living with little margin for loss.

The ensuing period became known as Móðuharðindi, the Mist Hardships. Roughly one-fifth of Iceland’s population died during the years of hardship associated with the eruption. A sulphurous haze also spread beyond Iceland across parts of Europe, demonstrating that the consequences of a major Icelandic eruption could extend far beyond the country in which it began.

This history changes the way Eldhraun should be read. The moss-covered surface may now appear quiet, but it is not simply an attractive roadside landscape. It is the surviving physical extent of an event that destroyed farms, disrupted communities and became one of the darkest episodes in Iceland’s recorded history.

Jón Steingrímsson and the Fire Mass

The best-known human account of the Skaftá Fires is connected with Jón Steingrímsson, the priest at Kirkjubæjarklaustur. He observed the eruption and recorded what happened as lava, ash and volcanic gases affected the district. His writings remain among the most important contemporary descriptions of the disaster and of the conditions endured by the people living through it.

Jón is remembered above all for the Eldmessa, or Fire Mass. As lava threatened the area, he continued a church service while the eruption unfolded nearby. The later tradition that the lava stopped as a result of the sermon became deeply rooted in Icelandic cultural memory, although the religious account and the geological explanation belong to different ways of understanding the event.

The story connects the immense scale of the eruption with one community and one recorded human voice. Eldhraun preserves the physical result, while Kirkjubæjarklaustur preserves much of the human memory associated with the advancing lava and the Fire Mass.

A hard landscape beneath fragile moss

The broken basalt of Eldhraun has gradually been colonised by moss. From a distance the vegetation makes the lava appear soft, but beneath it lies an uneven surface of sharp rock, cracks and hidden hollows. The contrast between that hard underlying structure and the moss above it gives the field much of its visual character.

The moss grows slowly and is easily damaged by foot traffic. A single crossing can crush the vegetation and leave a mark that remains visible for years. Much of the accessible field beside Route 1 is therefore fenced, and visitors should remain at the established stops and viewing areas rather than stepping onto the moss.

This restriction does not prevent a close experience of Eldhraun. The roadside stops provide clear views across the surface, and the repetition of moss-covered ridges and hollows becomes more apparent when seen from a fixed position. Respecting the access boundaries is part of understanding the landscape rather than an obstacle to it.

Reading Eldhraun from Route 1

Driving across Eldhraun reveals its extent, but movement can also flatten the field into a continuous band of moss beside the road. Stopping allows the surface to separate into individual forms and makes the relationship between the lava, distant ridges and nearby mountains much easier to see. The established roadside viewpoints are therefore valuable not because they isolate one celebrated feature, but because they give time to read a landscape built from repetition and subtle variation.

Season and weather change that experience considerably. Summer can bring stronger greens, while autumn and winter shift the field towards quieter colours. Snow settles unevenly across the lava, tracing its structure and dividing the surface into clearer shapes. Low sunlight strengthens the relief by placing shadow between the rounded forms, while overcast conditions suppress the larger contrasts and bring attention to smaller variations in moss and stone.

Eldhraun rewards close observation as much as a wide view. Its scale belongs to the eruption, but its present character is found in the small changes of form, colour and light across the surface. Both are visible from the roadside when enough time is given to looking.

• • Eldhraun was formed by lava from the 1783–1784 Skaftá Fires at Lakagígar.
  • Lakagígar belongs to the Grímsvötn volcanic system.
  • The eruption contributed to Móðuharðindi, the Mist Hardships, during which roughly one-fifth of Iceland’s population died.
  • Jón Steingrímsson’s account is one of the most important contemporary records of the eruption.
  • The Eldmessa, or Fire Mass, became the best-known cultural story associated with the advancing lava.
  • Eldhraun extends eastwards to the base of Lómagnúpur.