City north of Cologne (5)
I believe the answer is:
essen
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">city north of cologne</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for essen that I've seen before include "German industrial city on the Ruhr" , "Industrial city of northwest Germany" , "European city" , "Industrial centre of the Ruhr" , "Krupp HQ (Ger.)" .)