v 39 Grottutbildning i Korallgrottan

At the end of September, after a week of visting several companies in Östersund, we headed north to Stora Blåsjön to learn about caves and explore Sweden's largest cave system.

We met with our instructor, August, and hiked around Bjurälven to see the karstlandskap, which is a landscape where water interacts with the rock below creating sink holes (dolinar), sinking streams that disapper suddenly and continue underground, and cave systems. Some of the dolins were impressively large and there were other smaller ones that continue to grow. All these had been formed by water running underground and washing away the sand from underneath and sweeping it into the caves below.

We continued up to Korallgrottan where we were outfitted with knee pads, headlamps, helmets and sturdy overalls. We took our first trip into the caves, which have a consistent temperature of around 4 degree all year around, though some parts can have ice formations created near entrances.

We learned to navigate in the cave system which requires taking a 2-D map and translating into a 3-D reality. It was difficult and we were thankful to get August's advice here and there. It was interesting to learn about various features in the cave that indicate which way the water flowed based on erosion patterns and how fast based on the size of the erosion marks. August also talked about stalactites and stalagmites, which you can remember by knowing that stalactites grow from "taket" and stalagmites grow from "marken" (på svenska). Overall we learned a great deal about caves and the geology that creates them and how to safely explore caves. At then end of our tour, we bathed in the waterfall at one of the caves entrances, washing away a week of dirt from crawling around in the depths of Korallgrottan.