Ascetic at last departing for Ruhr location (5)

I believe the answer is:

essen

I'm a little stuck... Click here to teach me more about this clue!

'ruhr location' is the definition.
(city in the Ruhr region of Germany)

I don't understand how the remainder of the clue works.

Can you help me to learn more?

(Other definitions for essen that I've seen before include "Industrial city of northwest Germany" , "city in the Ruhr valley" , "European city" , "German industrial city on the Ruhr" , "Main industrial city of the Ruhr" .)

I've seen this clue in The Telegraph.

Want a hint initially instead of a full solution? Install my app