Þjórsárdalur valley

A sheltered valley between green land and volcanic ground

Þjórsárdalur lies between the southern lowlands and Iceland’s interior. The valley floor and surrounding slopes contain lava, glacial sediments, pumice and tephra from several volcanic events, while rivers descending from the highlands have cut channels and gorges through the accumulated material. This mixture prevents the valley from having one uniform appearance. Open volcanic ground can give way quickly to grass, low vegetation and woodland, and the more severe country towards Hekla remains visible beyond sheltered green areas.

The broad form of the valley is important to its identity. Individual waterfalls and archaeological sites draw visitors to particular points, but the spaces between them are not empty. Rivers, open land and long views towards Hekla keep the wider landscape present throughout the journey. Elevated positions help reveal this scale, showing how wooded areas occupy parts of a much larger volcanic setting rather than forming an isolated forest.

Búrfell becomes conspicuous towards the inner end of the valley, where the natural landscape also meets modern hydroelectric engineering. The mountain, power infrastructure and altered river system belong to present-day Þjórsárdalur, but their full history requires a separate destination page. Here they form a short final layer in a valley already shaped by medieval settlement, eruptions and extensive restoration work.

Woodland restored across a damaged landscape

Woodland is not merely decoration within Þjórsárdalur. Restoration and stabilisation work began in 1938 on land affected by pumice, erosion and the accumulated effects of human use. The purpose was not only to plant trees, but to rebuild vegetation and soil on ground that had become vulnerable. Over decades, birch woodland, planted trees and other vegetation created the green character now encountered in substantial parts of the valley.

This work gives the landscape a connection between past damage and future resilience. Hekla’s ash had repeatedly affected the valley, while loss of vegetation left parts of the surface exposed to wind and erosion. Restoring continuous plant cover helped stabilise that ground and made it better able to withstand later ashfall. The woodland therefore represents a managed recovery within an active volcanic region, not a return to an untouched landscape.

Sandártunga is one of the clearest places to experience this sheltered woodland character. Paths, stopping places and the camping area allow visitors to spend time among the trees rather than see them only from the road. It also provides a useful central reference point for a valley that has no single natural entrance or centre. Summer brings out the strongest relationship between the woodland, open grass and dark volcanic ground, making the season particularly important to the identity of Þjórsárdalur.

Hekla, medieval settlement and an incomplete story of abandonment

Hekla’s eruption in 1104 spread pumice and ash across the region and had severe consequences for farms in Þjórsárdalur. Volcanic material covered buildings and land, and it later helped preserve archaeological remains that might otherwise have disappeared through reuse, weather and erosion. The farm complex at Stöng provides the best-known physical evidence, but it represents part of a settled medieval landscape rather than one isolated household.

The older version of the valley’s history often presents the eruption as a single ending: farms were buried, the inhabitants left and Þjórsárdalur was abandoned. Archaeological and environmental research has made that account less absolute. Evidence of later human activity elsewhere in the valley means that settlement did not necessarily cease everywhere at the same moment or remain absent without interruption. The eruption was a major disruption, but the history that followed was uneven.

Stöng and the Commonwealth Farm allow visitors to approach this period in different ways. Stöng preserves authentic remains within their original landscape, including the plan of the farmhouse and associated working buildings. Þjóðveldisbærinn stands separately beside Road 32 and uses archaeological measurements and wider evidence to reconstruct a complete turf building. One site shows what survived; the other demonstrates the interpretation required to rebuild what did not.

Rivers connecting the valley’s different landscapes

Water provides the strongest physical connection between several of Þjórsárdalur’s destinations. Fossá descends from the interior and forms Háifoss, where the river plunges into a deep, exposed canyon beside Granni. Farther downstream, the same river divides around a central rock and creates the two cascades of Hjálparfoss within a much lower and more enclosed basalt basin. The contrast between these waterfalls shows how one river changes as it crosses different levels and rock formations.

Gjáin presents another relationship between water and volcanic ground. Its waterfalls, streams and vegetation are contained within a small side gorge, largely concealed until visitors approach its edge or enter on foot. The sheltered interior differs sharply from the open land around it, yet it belongs to the same wider system of lava, erosion and water. The individual destinations should be explored through their own pages, but the valley route makes their geological relationship easier to understand.

Þjórsá remains the larger presence along the eastern side of the valley. Together with its tributaries, it has influenced landforms, routes and modern energy development. For photography, the river landscape, Hekla and open land are the strongest subjects at valley scale. They allow the smaller green and wooded areas to be understood within the broad country that surrounds them.

A full-day journey through Þjórsárdalur

The most coherent route enters Þjórsárdalur from Árnes and works progressively into the valley before leaving past Hekla towards Hella. Hjálparfoss makes a natural early stop, followed by Þjóðveldisbærinn beside the paved road. Stöng lies farther into the valley on a rough road that can normally be driven in an ordinary car with care during good summer conditions. Gjáin lies beyond Stöng, where the route includes a creek crossing and a 4×4 should be regarded as necessary. A 4×4 is also the sensible recommendation for the rough access to Háifoss and Granni.

The roads to the inner sites should be treated as summer access. Conditions can change, and the ability to reach one destination does not establish that the continuation will be suitable for the same vehicle. Hjálparfoss has the most dependable visitor facilities within the route. Sandártunga provides woodland recreation and camping, but facilities and seasonal services should be checked rather than assumed when planning the day.

A full day is sufficient to see all five principal destination sites without automatically reducing the valley to a rushed checklist, provided the journey begins early and conditions are suitable. Þjórsárdalur can also be incorporated into a route towards Landmannalaugar, but using it only as a corridor risks missing the relationship between its woodland, archaeology and rivers. The valley is strongest when the journey itself is treated as the destination and the separate stops are allowed to build a connected account of the landscape.

Recreational drone flying is prohibited within the protected landscape and at the signed natural monuments and archaeological sites. Aerial photographs can still be valuable for explaining the valley’s scale when they were made lawfully or with the necessary authorisation, but visitors should not interpret their presence on the page as permission to fly recreationally.

• • Þjórsárdalur’s protected landscape covers approximately 58 square kilometres.
  • Woodland restoration and land stabilisation began in the valley in 1938.
  • Thick volcanic deposits record repeated eruptions, including the major effects of Hekla’s eruption in 1104.
  • Stöng and Þjóðveldisbærinn are separate destinations: one preserves excavated medieval remains, while the other is a modern reconstruction.
  • Fossá forms both Háifoss and Hjálparfoss in very different parts of its course.
  • Gjáin, Háifoss and Granni, and Hjálparfoss have additional protection as natural monuments.