Reykjadalsá, the hot river

Park near the Delakaffi café, at the southern end of a long car park.

(S/E) Head to the northern end of the car park to find a sign with a map of the area and information on the geology, flora and fauna. Then continue northwards.

(1) Cross the river via the wooden footbridge, pass to the right of a sheep sorting pen, then take the wide, steeply sloping path.

(2) At the right-hand bend, a few metres to your left, a first “marmite” of bubbling mud^(a) with abundant sulphurous vapours is worth a detour (take care, especially with children).
Continue the climb; the slope is steep and the stony path slows you down. Take a break to turn round and admire the magnificent view towards the town and the ocean to the south.
The slope levels out and the path narrows. A balcony-like section offers the chance to enjoy a remarkable view.

(3) Below on the left, admire the Djúpagil canyon and waterfalls into which the Reykjadalsá flows^(b); further west, at the bottom of a valley, you can see abundant fumaroles^(c).
A few hundred metres further on, on a sort of plateau, the terrain is greener and the river winds through the meadow.

(4) Take the footbridge on the left. A sign indicates that you can swim in the river 700 metres ahead.
Geothermal features are becoming increasingly numerous and intense: pools of various colours, fumaroles, mud holes and bubbling water.

(5) A little further on, a dense, damp, warm, sulphurous cloud hangs over the path. You just need to watch your step and watch where you put your feet. After this stretch where you have to hold your breath, a short descent leads to a place called Klambragil, on the right bank of the river towards a wooden footbridge. The water temperature here is around 35°C.

(6) Enjoy a swim to your heart’s content.
On each bank, the path is covered with wooden duckboards and steps make it easy to get down into the shallow river. A few rudimentary screens provide privacy for changing.
The water temperature, averaging 38°C, depends on the season and increases as you head upstream.

^The changeable weather often forces^you to cut short the particularly relaxing swim for a hasty return. Otherwise, you can extend the route with a circular loop. Head upstream from the left bank, then leave the wooden decking for a footpath.

(7) The path soon leads to the junction of the Ölkelduhnúkur circular loop, which is about 3 km long; choose whichever direction you prefer. You will see numerous solfatara^(e) and other geothermal features.
Then return to the Klambragil footbridge.

(6) You have two options. If it is raining, take the same route you took on the way there. If conditions allow^, you can head back along the left bank of the river (route marked on the map) and further on, on the plateau, you will find the footbridge over the Reykjadalsá.

(4) The Reykjadalsá on your right flows towards the Djúpagil canyon and its waterfalls. Continue along the path you took on the way there, this time enjoying the view to the south. As you approach the car park, note the streams with their striking colours (S/E).

It is also possible to start the hike at the northern end, but on some days there are many Icelanders and tourists.

In wet weather, the ground is slippery and in winter the path is not cleared of snow. It is recommended not to stray from the path, out of respect for the flora and for safety reasons, as the ground is unstable in places, particularly near the mud holes and pools of boiling water.

(a) Bubbling mud pots: in the solfataric fields (see (e)), one sometimes sees pools of mud that are more or less viscous, bubbling, steaming and foul-smelling. They are formed by the action of hot, acidic water on the rocks. Often, bubbles of carbon dioxide rise and burst on the surface.

(b) All Icelanders speak English. However, some information or signposting boards use onlythe Icelandic script, the pronunciation of which is not easy for the uninitiated.
Ð or ð is roughly equivalent to the English ‘th’.
Á or á are pronounced ao.

(c) Fumaroles: the term is rather overused and refers indiscriminately to any gaseous emission from a hydrothermal system.
For scientists, fumaroles refer to gas emissions between 300 and 1000°C that accompany volcanic eruptions.

(d) Icelanders are fond of saying: if you don’t like the weather, wait five minutes and you’ll be delighted. The trouble is that when you do like the weather, five minutes later...

(e) Solfatara vents consist of 90% water in the form of steam, and various components: carbon dioxide, methane, hydrogen sulphide… at temperatures between 100 and 300°C. They are generally surrounded by sulphur deposits formed by the reaction of hydrogen sulphide with the air. There are also various deposits (clay, sulphur compounds, sulphates...) which give the solfatara magnificent shades of yellow, ochre and red.
Solfataric fields often emit fascinating sounds and foul odours reminiscent of rotten eggs.

(f) The path is not recommended in wet weather and is sometimes closed to protect the flora or for safety reasons.

Dalakaffi, bar and light refreshments. Closed in winter.

The definitions are taken from planet-terre ens Lyon.

Visit to Hveragerði and in particular its geothermal park located in the centre.
Town map.

Map of the trails north of Hveragerði.