Nobody knows for sure when they started to break ore in Tuna Hästberg. Some sources indicate that the first mines were mined already in the middle ages. However, it is more likely that they first mining began during the 16th century or the beginning of the 17th century. Certainly, we know that in the late 16th century there was a cottage for the production of pig iron production in the nearby Laxsjön and a few decades later, around 1640, a cabin had been built at the nearby lake Rämen. The ore to the cabins retrieved the owners from most nearby mines, including Hinzgrufvan, which appears on a parish map of the Tuna parish from 1648.
In Tuna Hästberg you have broken iron ore, magnetite, also called black ore, with elements of manganese. The ore has low phosphorus content and could thus be used at the old cabins already far back in time. The field consists of six superimposed ore bodies, where the so-called Kronmalm gave the field’s richest ore with up to 54% pure iron. The bodies lean from the surface 30-45 degrees but flatten toward the depths and lie almost horizontally in their places. Around 360m, the bodies lean for example between 0-30 degrees to the depths. In their places some of the bodies are so close that they are broken as if they were a single ore body. This gives rise to powerful and impressive breakthroughs, such as the great “Indy Hall”. The strength (ore body thickness) has reached 75m in its places.
Even though it broke ore in Tuna Hästberg for hundreds of years, the mine did not experience its greatness until the 20th century, when major capital initiatives were about modernizing and streamlining mining in the village. From the mid 30’s all operations were taken over by Stora Kopparbergs Bergslags AB, which needed the manganese iron ore for its ironworks in Borlänge, Domnarvet. Stora propelled the mine until the final closure of summer 1968 and hence a centuries-old mine had ended. Over the years some 6 million tonnes of ore were broken in the mine, but it is estimated that significant assets, at least 16 million tonnes, remain in depth.
In the mountain there are several kilometers of tunnels, giant breaches and remains that last a long time when both the mine and the village are alive.
In 2011, what we called today called the Adventure Mine. The adventure mine is an economic association. After the opening ceremony, the business has expanded every year and today the main activities of guided tours in the dry-laid environment range from simple hiking tours to more advanced adventure tours with climbing on our extensive Via Ferrata, as well as diving in the water-filled part of the mine. Our vision is that the mine should be left as untouched as possible. Instead, we adapt our visitors to the mining environment, by equipping them with a helmet, bulb and harness when required. Read more in our experiences.