Merkurker; the Cave That is Not

Merkurker, Þórsmörk, Iceland: a place full of wonders, a place full of myths and lore, a place created by some of nature’s strongest forces. Þórsmörk is a national park that has been under the protection of the government run Icelandic Forest Service (Skógræktin) since the year 1924 (Skógræktin, 2017). This is a place that has strong cultural ties and is today one of the most frequented natural preserves in the country, be it for camping, hiking or taking pictures. Internationally this place is perhaps the most known for the 2010 volcanic eruption in Eyjafjallajökull which stopped air traffic around the globe for days (Haraldsson, 2010). I have been lucky enough to get to visit this place for at least one night every year; this night is midsummer night, or as we call it Jónsmessa. A night where “cows develop the capacity of speech and seals take on human form” (Iceland Magazine, 2016); a night where we believe the elves come out to dance with us and we sing songs and celebrate in “true” Viking fashion with mead (if you are off age, of course) and a big campfire. But this is a great big place and there are a couple of more treasured spots within the national park; Merkurker is one of them.

As you drive south from Reykjavík, the capital of Iceland, after about an hour and a half’s drive you will reach a tall waterfall, Seljalandsfoss, surrounded by green grass, plenty of tourist busses and a campsite. When you reach the waterfall, take a left turn, you have now reached the boundaries of Goðaland, or the land of the Gods. Drive on for around 30 more minutes, be careful, you will now have to pass numerous streams of a braided river along with smaller meandering rivers. Depending on the season they might be deep and hard to cross, do not attempt this unless you are driving an SUV. As you drive further along the road you will start to see the river paths that Markarfljót has created to the left, this is a braided glacier river, a river that is ever changing. A river that has created great devastation for the local communities and just recently carved out new paths destroying archaeological remains. The sudden changes in the river has created stories of a river monster hiding within its midst. As you continue your drive you will see more rivers and how they have impacted the surrounding areas, leaving behind only sand and the scarce large stone. You will also see a couple of mountains, Stóri-Dímon and Litli-Dímon, mountains that were the scene of battle for one of the most renowned Icelandic Sagas (Ólafsdóttir, 1994). On your right, you will see mountains start to form, it is by one of these mountain cliffs, Sauðhamrar, that you will stop by a river named after them, Sauðá. Park your car on the gravel by the river, step out of it and now walk up the river until you reach the cliffs (Picture 1 in Appendix). There will you find a path which will lead you into a valley with a river going through its midst.

You have now entered Merkurker. Looking down you can see two “islands” of gravels separated by a river, a river that leads into what seems to be a cave (Picture 2 in Appendix). This is the main attraction of Merkurker. As you walk down from the end of the path, towards the gravel island closer to you, you will notice various species of moss growing in the hills surrounding the small valley, along with grasses and smaller flowering plants. As you walk down, what takes your interest will most likely be the river, where does it lead? Does it just stop as it reaches a wall in the cave? Here is to hoping that you brought a flashlight, a good pair of wading shoes and a travel partner, as this should not be explored on your own. As you step into the water, even in the midst of July, you feel that it is freezing cold (around 5°C), as it is a springfed river and keeps around the same temperature all year round (Náttúrufræðistofnun Íslands, Unknown). The cold makes you want to start to immediately move so you start carefully making your way down the river. As you walk down the river — over the time of approximately 10 minutes, but what seems like an eternity — you can feel how the rocks in the bottom have been rounded by the force of the river and how the water has been given more resistance at some places and less at others, creating deeper pools where the water will reach your waist and shallow spots where the water will only reach your ankles. You can now see that you have found what seems like the solution to the mystery, this was indeed not a cave, this was a tunnel created by the force of the water, a force that has been there for hundreds of years, slowly breaking its way through the rock. As you make the last dip into a deep pool of water after having climbed over a couple of large rocks you have entered what is now the end of the tunnel. Here you have reached the second small valley, just like the one you walked down into before you entered the river. As your eyes trace the rest of the way of the river you can see how it goes through a small crack in the cliff in front of you, joining what you assume is Sauðá.

You have now experienced one of the wonders of Iceland, walked through many of the naturally created river tunnels, in the area and in the country. You have found a solution to your mystery, you now know that a river can seemingly create a tunnel. But how does it do it? Why is this plant life here and what other elements might have worked with the water to create this wonder of nature?

Iceland is an island formed by volcanic activity on the divergent border of the North-American tectonic plate and the Euro-Asian tectonic plate (Iceland on the Web, Unknown). As the plates moved apart the lava created an island, a process which is still in process today and the island expands a couple of centimetres each year. As the island was created by volcanic activity most of the rock found there is igneous rock. A rock type which is clearly eminent in Merkurker, the main cliff formation that Sauðá has cut through is a big chunk of an igneous rock by the name Tuff. This is on the mother tongue of the country called Móberg, which refers to the plant life often found growing on and near the rock. Þórsmörk is all covered in tuff, which is found in layers upon layers after different volcanic eruptions, which built up till the ice age. During the ice age Þórsmörk, as well as the rest of the country got covered by a thick ice sheet. As the ice sheet melted and moved across the landscape the rocks got shaped by the shear pressure of the weight and the rivers and streams that came from the glaciers (Ólafsson, 2001). This is very apparent in the landscape of Þórsmörk. When you enter Merkurker you can see this on a smaller scale. Here you can see how the river has slowly made its way through the cliff and expanded what was once a small crack into a tunnel you can now walk through. As mentioned earlier the rocks on the bottom of the river are now rounded by the endless stream of water passing over them.

On the outer sides of the cliffs and down by the river banks you can see various types of grasses, mosses and heathers that will be full of berries in the fall. These plants are found all over Þórsmörk and have especially grown well after the nutritious ash fell in the 2010 volcanic eruption. These berries and grasses are then feasted on by, especially sheep and human beings. The humans that pick them for teas and dry them and use for spices on their lamb meat – the lambs – which sarcastically feasted on the same plants when they were living the summer before; Talking about being spiced in and out. As this area is well known amongst Icelanders it has now become a major tourist attraction for tourist agencies to point out. This means that there is a lot more erosion today than there was 10 years earlier. This means that there is also fewer opportunities to catch a glimpse of the wild animals, such as foxes that lurch around the area, but are hostile towards humans.

Merkurker is a little speckle of natural wonder in the midst of Iceland. The geological significance of the country perhaps makes it seem insignificant. However, it displays and makes it easier to understand on a smaller scale how the natural forces work with and against each other. Such as how water weathers down the rock and always finds a way to get where it “feels a need to go”. The travel to the spot is in my opinion just as important as the spot itself. When you drive out of the city, you can see the variation in the landscape, you can see the valleys and mountains that have been created by thousands of years of weathering. Coming to Merkurker where you can see it on a smaller scale, right in front of you makes you understand how powerful the force of water is. Iceland is the country of fire and ice. And it is through the means of spots such as this one that you really start to understand how the two work together to create something as beautiful as Merkurker.



Haraldsson, Ó. (2010, Maí). Eyjafjallajökull. Retrieved from Eldgos:

Iceland Magazine. (2016, June 24). Jónsmessa. Retrieved from Iceland Magazine:

Iceland on the Web. (Unknown). Volcanism. Retrieved from Iceland on the Web:

Náttúrufræðistofnun Íslands. (Unknown). Ár og Vötn. Retrieved from Náttúrufræðistofnun Íslands:

Ólafsdóttir, R. (1994). Leiðarlýsing Inn Á Goðaland. Retrieved from Útivist:

Ólafsson, G. P. (2001). Hálendið í Náttúru Íslands. Reykjavík: Mál og Menning.

Skógræktin. (2017). Skógræktin. Retrieved March 18, 2017, from Suðurland: Þórsmörk:

Sverrisdóttir, A. M. (n.d.). Merkurker. 2015. Þórsmörk.



Picture 1

View from the edge of Sauðhamrar (Sverrisdóttir)

Picture 2

Looking down into the rift valley, Merkurker (Sverrisdóttir)