Greece advanced Spanish nothing for their city (7)
I believe the answer is:
Here is my best explanation:
'their city' is the definition.
I can't judge whether this definition defines the answer.
'greece advanced spanish nothing' is the subsidiary indication.
'greece' becomes 'gr' (abbreviation).
'advanced' becomes 'a'.
'spanish nothing' becomes 'nada' ('nothing' in Spanish).
'for' is the link.
(Other definitions for granada that I've seen before include "City in southern Spain, site of the Alhambra", "Spanish city, site of the Alhambra", "car in > Spanish city", "City of Andalusia", "city in Spain", "Andulasian city", "sunny city" and "Andalusian city".)