Area with great resources but not one sign of McDonald’s (6)
I believe the answer is:
arches
'area with great resources but' is the definition.
I can't judge whether this definition defines the answer.
'one sign of mcdonald's' is the wordplay.
I cannot quite see how this works, but
'one' could be 'a' (a thing is one thing) and 'a' is located in the answer.
'sign' could be 'he' (he is a kind of sign) and 'he' is located in the answer.
The remaining letters 'rcs' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
'not' is the link.
Can you help me to learn more?
(Other definitions for arches that I've seen before include "Curved under-parts of the feet" , "Search (anag.)" , "Curved structures" , "Vaults" , "Curved shapes that span openings" .)