Neighbourhood around northern sports venue (5)
I believe the answer is:
arena
'sports venue' is the definition.
(I've seen this before)
'neighbourhood around northern' is the wordplay.
'neighbourhood' becomes 'area' (a neighbourhood is an urban area).
'around' is an insertion indicator.
'northern' becomes 'n' (abbreviation e.g. N. Ireland).
'area' placed around 'n' is 'ARENA'.
(Other definitions for arena that I've seen before include "Place for public events" , "Gladiatorial venue" , "Ring; stadium" , "Venue for contests" , "Place of combat" .)