Dusseldorf is on it (5)
I believe the answer is:
rhine
(Other definitions for rhine that I've seen before include "Cologne's river" , "Great German river with Lorelei Rock" , "River of Cologne" , "valley" , "water" .)
I believe the answer is:
rhine
(Other definitions for rhine that I've seen before include "Cologne's river" , "Great German river with Lorelei Rock" , "River of Cologne" , "valley" , "water" .)