In this year's summer, we made hiking holidays in the Harz region in Germany. During these holidays we also visited the "Tagebau Elbingerode", an open-cast limestone mine near the old town of Elbingerode.
Here's the story I wrote about this hike: https://www.schmatz.cc/trips/der-tagebau-in-elbingerode/
More about Harz: https://en.wikipedia.org/wiki/Harz