Documentary evidence for the Markus Semmler adit dates back to 1503. It was originally opened near Oberschlema to mine copper. Later, it served the bismuth, silver, cobalt, and nickel mines all around Schneeberg. In the 19th century, the new adit mouth was built. It is dated to 1841 by the keystone on the construction. By the end of the 19th century, the adit extended over roughly 43 kilometres. During the second half of the 20th century, the adit was the first important exploration site used by SAG/SDAG Wismut in the search for uranium. It was used as a reference line for all deeper excavations. From 1946 onwards, a further 174 kilometres of mine workings were cut at roughly the level of the Markus Semmler adit. The adit continues to drain water from the entire Schlema, Schneeberg, and Schneeberg-Neustädtel mining district today.