Not so much need to know, but nice to know

Not so much need to know, but nice to know

By Jóhannes M. Jóhannesson

We couldn’t possibly share with you all the information about the cave during our tours, so we would like to share some of them with you here. This is some general information about the cave, for more specialized info have a look at the other chapters on our blog. 

The Cave Víðgelmir lies about 33 kilometres away from the craters that formed the lava field, and they sadly cannot be seen from the cave (for more information on the lava field itself, see chapter “Hallmundur and Hallmundarhraun” on the same webpage). The total length of the cave is 1585 meters, split into two sections by the opening. One short section leads about 60 meters further up the field, while the longer section wiggles its way down the field. It is the second longest cave in Iceland, with Surtshellir being the longest one at about 1970 meters long. The Cave Víðgelmir has an average height of 9,2 meters, with the maximum height being 15,8 meters and the minimum height being about 0,5 meters (no need to worry as we don’t go through that sections, so no crawling involved). The average width is 10,2 meters, with the maximum width being 16,5 and the minimum about 0,5 meters (same section as before, so no need to worry). The Cave Víðgelmir is therefore the largest cave in Iceland in terms of volume, at about 148,000 cubic meters. (Hróarson and Jónsson, n.y.). It also has one of the thickest ceilings of all the caves in Iceland, and as we walk through the cave, we’ll have about 5 to 25 meters of ceiling thickness above us. The opening of the cave is also very large, about 75 meters long and 15 meters wide (Björn Hróarsson, 2008). The opening tends to be semi-filled up with snow during wintertime and during cold periods (lasting few years to a few decades), a section of the cave called the “squeeze” and/or “vatnslás” can be filled up with ice. That ice does not melt during the summer time, and effectively closes the cave. Once these colder periods end, the ice melts away and the cave opens again. This has happened twice in recent history, between 1918 and 1930 and again between 1972 to 1991. Just before the cave became inaccessible in 1972, it was mapped for the first time by the Shepton Mallet Caving Club. The cave opened again in 1991, but the cave did not open itself naturally, the Icelandic speleological society along with a few locals broke their way through the ice, starting in the spring of 1990 and finally got through in 1991. Due to the way caves were being treated in Iceland at that time, it was decided that this cave should not be open to the public, and therefore an iron gate was installed in the squeeze to prevent people from entering it (Hróarson and Jónsson, n.y., Björn Hróarson, 2008, Guðmundur Ólafsson, 1998). Since 1991 there have only been guided tours into the cave, to allow people to experience the greatness of this cave without harming the fragile lava formations found in there. The cave was then mapped for the second time in 1996, by the Icelandic Speleology Society (see Fig. 1). 

The benefit of the cave having been mostly inaccessible and then only with guided tours for the last few decades, is that this cave is by far the best-preserved, large, accessible cave in Iceland. Sadly we, the Icelandic people, have not treated our caves very well, and many lava caves in Iceland have been badly damaged and lava formations, such as stalactites and stalagmites, have been broken and removed from them. In Víðgelmir however, most of the stalactites and stalagmites remain due to the preservation of it. This company now runs daily tours into the cave (see our website for further details) called The Cave Explorer. The duration of the tour is an hour and a half, and we go about 600 meters into the cave (see Fig.1)

 

Vidgelmir map 

Fig.1. Map of the cave Víðgelmir, showing the entrance of the cave, where the small section called the squeeze is, and how far the cave explorer tour goes into the cave. Fig from the Icelandic Speleology Society of Iceland. 

 

We are often asked why we do not go further into the cave than the 600 meters, and there are two reasons for why. First, after spending an hour or so inside the cave most people have gotten fairly cold and are ready to head out into the warm sun (which doesn’t happen that often up here though), second, the lava formations at the back end of the cave are so well preserved that we want to limit the amount of people who go through there. We do have The Cave Master tour, but it is only meant for people with background in geology. You will see everything that the cave has to offer in the first 600 meters, but the master tour is for people that want to see more of the cave and get to know (a lot) more of the geology of the cave itself and lava caves in general. 

And finally, as we get asked this a lot, is the dog (that you will most likely meet at our service house) coming to the cave with us and why is he not going with us? The dog is a he btw, and not a puppy any more (although he acts like one) as he just turned 5 years old. He has the very friendly and easily pronounced name „Hrammur“ (rolls of the tongue I know), which basically means a large paw. He does not go with us on the tours, as he gets easily bored in there and knows no one is going to be able to play with him there so he can’t be bothered.  

 

 

References and further reading:

Björn Hróarsson (2008). Hellahandbókin leiðsögn um 77 íslenska hraunhella. Mál og menning, Reykjavík. 

Björn Hróarsson og Sigurður S. Jónsson (ny). Lava caves in the Hallmundarhraun lava flow, western Iceland. 6thinternational symposium on Vulcanspeleology. 85-88

Guðmundur Ólafsson (1998). Fylgsnið í hellinum Víðgelmi. Árbók hins íslenzka fornleifafélags, 125-142, 94. árg.