Old fogies wandering around south London neighbourhood (4,2,4)
I believe the answer is:
isle of dogs
'london neighbourhood' is the definition.
(Isle of Dogs is an area of London)
'old fogies wandering around south' is the wordplay.
'wandering around' is an anagram indicator (I've seen this in other clues).
'south' becomes 'S' (abbreviation).
'old'+'fogies'='oldfogies'
'oldfogies' is an anagram of 'isleofdog'.
'isleofdog'+'s'='ISLE OF DOGS'
(Other definitions for isle of dogs that I've seen before include "London district" , "East London area" , "East End venue" , "Part of London" , "Thames peninsula, opposite Greenwich" .)