Železná hůrka is a Quaternary volcano of similar scientific importance as the nearby Komorní hůrka. It is mentioned by J. W. von Goethe, who had slag brought down from the summit, believing it to have originated as coal heated up underground. The site is protected as a national natural monument. Volcanic products can be found on the site of the original crater and in the vicinity; it is so far the most recent volcano in the country.

In his diaries from 1822–1823 von Goethe writes about repeated visits to Starý Albenreuth (now Mýtina), the nearest village to Železná hůrka. At that point in his life the ageing poet and natural scientist spent far less time exploring the countryside than he used to and samples were brought to him by his friends or people hired to find them. He assumed that the typical slag rocks he was brought came from Železná hůrka. However, the samples from his mineralogical collection preserved in Výmar that were found at this site do not resemble those from Železná hůrka, but are similar to the pyroclastics from the recently (2009) discovered Mýtina crater, which is the most recent volcano to have been described in this country. While the typical shape for Železná and Komorní hůrka is a slag cone, the Mýtina crater is what is known as a maar, a funnel-shaped crater several hundred metres in diameter, which later filled up with water, and is characterised by its lake sediments that form the filling of the original crater. This crater shape is formed when magma comes into contact with a water-saturated environment as it passes through the rock, causing a massive explosion. A Maar may appear as a ring of original volcanic pyroclastics – essentially the banks of the flooded crater. The pyroclastic samples that von Goethe possessed led him to (incorrectly) conclude that the basalt was of non-volcanic origin. According to F. A. Reuss, he considered the local slag to be “pseudo-volcanic”, or the products or natural underground fires. Volcanic material was mined on Železná hůrka until the 1950s. After a detailed geological survey a motion was filed to have it protected, and in 1961 it was declared a national natural monument. However, until 1989 it was situated in the border zone and was unknown to the public for a long time. The Mýtina maar crater was also hidden away in a similar manner. Its recent discovery is the continuation of the story of the search for the origin of the rocks, commenced by von Goethe two centuries ago in the landscape around Cheb.

 

Hošek, J. et al. O vulkánech netušených – nově objevené sopky v západních Čechách. Vesmír 99/ 498, 2020/9. URL: https://vesmir.cz/cz/casopis/archiv-casopisu/2020/cislo-9/o-vulkanech-netusenych.html [12. 2. 2021].

Mrlina, J. et al. Discovery of the first Quaternary maar in the Bohemian Massif, Central Europe, based on combined geophysical and geological surveysJ. Volcanol. Geoth. Res. 182, 97–112, 2009.

Národní geopark Egeria – Železná hůrka. URL: http://www.geopark.cz/zelezna-hurka [12. 2. 2021].

Urzidil, J. Goethe v Čechách. Příbram 2009, s. 398–403.