Capital is large, sprawling (7)
I believe the answer is:
algiers
'capital' is the definition.
(capital of Algeria)
'is large sprawling' is the wordplay.
'sprawling' indicates anagramming the letters.
'is'+'large'='islarge'
'islarge' is an anagram of 'ALGIERS'.
(Other definitions for algiers that I've seen before include "NW African capital" , "North African port" , "North African capital" , "N. African port" , "Capital city" .)