Chief coalmining and industrial region of Germany (4)

I believe the answer is:

ruhr

(Other definitions for ruhr that I've seen before include "German industrial region" , "industrial valley" , "German river flowing into the Rhine" , "German industrial zone, river" , "Ger. industrial region" .)

I've seen this clue in The Mirror.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.