Graendalur is a green valley north of Hveragerdi in the Hengill region, where geothermal activity and lush vegetation meet. Hot ground, steam and other signs of geothermal activity occur in the valley and surrounding area. It is a popular outdoor destination, but geothermal habitats and vegetation are sensitive to trampling. Graendalur forms part of the wider Hengill geothermal system and provides a good example of how geothermal heat can influence water, soil and plant life. Visitors should use established walking routes.
Hot springs
Fumaroles
Steam vents
Sulfur deposits
Parking
Hike required
Marked trail
Warning signs
Stay on marked paths
Geothermal features
A green valley in the Hengill region with hot ground, steam and geothermal habitats in varied hiking terrain.
Safety
Use established trails and avoid soft or visibly hot ground. Protect fragile vegetation and geothermal habitats.
Last verified 18 September 2026 Source