The mine at Lekomberg was once a fairly large one with a history going back to the early 1600s. Like many other medium-sized ones, it was acquired by the German steelworks giant Hoesch back in 1910, where the mine was extensively built out and modernized. Presumably, a fair amount of German cannons during the WWI were made with iron from this mine.

After some tough years in the 1920s and early 1930s, the build-up of the Nazi army in the mid-1930s heavily increased demand for iron and a new investment was done in 1938, where a 650 meter long tunnel was excavated into the rock under the concentration plant. Now, trains could be backed into the tunnel and loading could be done from an underground storage all year around without the usual problems of the wet concentrate freezing in wintertime. We all know what happened in the years to come and it is a fair guess that more than one Panzer were made with iron from here...

With the collapse of the German steel industry in late 1944, the mine was closed and the workers were laid off. The operation in the mine was never resumed, but the concentration plant and the tunnel was used for a few more years with new owners, fed with ore from adjacent mines. The operations finally ceased in the early 1950s and all buildings were torched and the remains bulldozed.

Today, there are almost no remains left. The tunnel is now water filled and it was somewhat a challenge to get in there. Anyone considering doing the same should be aware of the lack of oxygen in there. It's just a stub with no circulating air. Some decomposing stuff makes it very hard to breathe - presumably dangerous and/or stupid indeed and the visit was therefore quick.

Given the time it must have taken to fill each ore car, it must have been a hell of a place to work in when the steam locomotive filled the tunnel with their smoke...
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