We went to Folkwang musuem of modern art and the Zeche Zollverein.
The latter is the coalmine, an impressive assortment of buildings, towers, chimneys, conveyor bridges and rusty machines. The sketch shows the locomotive once used to catch the hot cokes from the cokesovens.
A sentimental journey; we had a coalmine with the same ovens just around the corner, within a kilometer of my house. But here in NL they choose to get rid of everything, there is nothing left now. Just memories.