Steinknochen Mining District and the Starý Martin adit
The Steinknochen Mining District, situated to the north of the town of Krupka, was the most important part of the Krupka Mining Area where more than 150 tin mines have operated from medieval times until the 18th or early 19th century. The density of mine workings is exceptional, not only in comparison to other mining districts in the Ore Mountains but in the whole of Europe, too.

Well-preserved medieval mine allotments, referred to in the Krupka mining code of 1487 and which have not yet been found elsewhere, characterise numerous remains of old workings. Shaft hollows and adit mouths are accompanied by flat-topped and terraced heaps with large upper platforms that have been well-preserved. These are clearly visible on old maps and current airborne laser scans. The distance between the heaps approaches the size of the old allotments referred to in the mining code: 36 x 36 m or, alternatively, 72 x 36 m.

The Dürrholz drainage adit, driven in the second half of the 15th century, is currently inaccessible from surface, but accessible via a short connection from the much younger Starý Martin adit that was in operation from 1864 until the 1980s. The latter exploited the Lucas lode, the district’s main tinand tungsten-bearing lode that has a strike of around 2 km, the longest tin ore vein in Central Europe. Mining ceased in the 1980s and, since 2000, the Starý Martin adit now serves as a mining museum that offers guided tours and a permanent exhibition of mining tools.

An old miners’ trail between Krupka and Horní Krupka crosses the eastern part of the Steinknochen district. This was used for the transport of ore and as an access to the mines. On the parapet near the trail, stones have been found dated to 1765 and 1894, but the trail must have been built much earlier. The Krupský potok creek, from which tin ores were panned, flows in parallel with the trail.