Hreðavatn Lake
About Hreðavatn Lake
Hreðavatn is a lake in the Norðurárdalur valley of West Iceland, just off the Ring Road at Bifröst and about 1 hour 45 minutes north of Reykjavík. It is roughly 5 kilometers long and up to 20 meters deep, with birch and conifer woods along much of its shore and the mossy Grábrókarhraun lava field running down to the water on the other side. Most drivers on Route 1 pass it without stopping, which is a good part of its appeal.
The lava came from the Grábrók craters beside the Ring Road a few minutes north, and the flow is credited with damming the hollow that now holds the lake. Two small wooded islets, Hrísey and Álftahólmi, sit out in the water. Local legend says a creature lives in Hreðavatn as well, though nobody claims to have seen it lately.
Walking trails start from Bifröst and lead through the woods and lava to the Grábrók craters, the Glanni waterfall on the Norðurá river and the green lava hollow of Paradísarlaut. In the hills nearby, plant fossils show that trees now found mainly in southern Central Europe once grew here. An attempt to mine lignite near the abandoned farm Hreðavatnssel ended when its tunnels collapsed.
June to September is the best time for a walk by Hreðavatn, when the birch is in leaf and the paths are dry. Allow an hour for a short stroll along the shore, or half a day if you link it with Grábrók and Glanni. Borgarnes is about 35 minutes south if you need supplies or a place to stay.
Good to know
Where is Hreðavatn?
Hreðavatn is in the Norðurárdalur valley in West Iceland, next to the village of Bifröst and just off the Ring Road between Borgarnes and the Holtavörðuheiði pass.
How was Hreðavatn formed?
Lava from the Grábrók craters flowed across the valley and is credited with damming the hollow that holds the lake. The Grábrókarhraun lava field still reaches the shore.
How big is Hreðavatn?
The lake covers about 1.14 square kilometers, is roughly 5 kilometers long and is up to 20 meters deep. It lies about 56 meters above sea level.
Can you hike around Hreðavatn?
Yes. Trails from Bifröst lead through the woods and lava near the lake and on to the Grábrók craters, the Glanni waterfall and Paradísarlaut.
How far is Hreðavatn from Reykjavík?
It is about 1 hour 45 minutes by car from Reykjavík on the Ring Road, and about 35 minutes north of Borgarnes.
What is there to see near Hreðavatn?
The Grábrók craters, the Glanni waterfall and the lava hollow of Paradísarlaut are all within a short drive or walk, and the cone-shaped mountain Baula rises to the northeast.
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