Agonised redeveloping coastal location (3,5)
I believe the answer is:
san diego
'coastal location' is the definition.
(city on Californian coast)
'agonised redeveloping' is the wordplay.
'redeveloping' indicates anagramming the letters (I've seen 'redeveloped' mean this).
'agonised' anagrammed gives 'SAN DIEGO'.
(Other definitions for san diego that I've seen before include "Calif. naval base" , "Southern California naval base" , "Pacific port" , "US city" , "Californian port" .)