The so-called Forest tin mines were found in the forests of Krušné hory between the towns of Boží Dar, Horní Blatná and Přebuz. Sněžná hůrka was an important district between the extinct settlements of Bludná and Háje, where the veins Zuzana (Susanne), Vavřinec (Lawrence), Trojice (Trinity) and Svatý Duch (Holy Spirit) were mined in the 16th century. The veins on the south east slope of Sněžná hůrka were opened by the Volská (“Ox”) Gallery. By the beginning of the 17th century, the richest ore deposits we exhausted to the depths of more than one hundred meters. In the 18th century, the mines were re-opened, but without major success.
The mine in the vein Zuzana was the largest one and its open cuts still remain till now. Especially stunning is about one meter wide excavation with length of about 150m and depth of 30 m. The handmade excavation has vertical walls with remains of side workings. The miners followed the so called gangue greisen - rock composed of quartz and mica enriched by fluorine, lithium and certain metals, especially tin and tungsten. The surrounding rock is coarse-grained biotite granite with abundant tourmaline, which is part of the younger intrusive complex of Karlovy Vary massif.
The location is outside the marked hiking trails and bicycle paths. This can be seen as positive fact, because it is a very dangerous place for uninformed visitors. In summer, the ravine is, in some places, completely masked by high grass and in winter with snowdrifts. The safety precaution of wooden railings may not be so effective as the structure is very similar to normal fencing.