Hired gun running amok round British city (9)
I believe the answer is:
Here is my best explanation:
'city' is the definition.
(Edinburgh is an example)
'hired gun running amok round british' is the subsidiary indication.
'running amok' indicates an anagram.
'round' is an insertion indicator.
'british' becomes 'b' (abbreviation e.g. in 'BBC').
'hiredgun' anagrammed gives 'edinurgh'.
'edinurgh' going around 'b' is 'edinburgh'.
(Other definitions for edinburgh that I've seen before include "Capital city of Scotland", "The capital of Scotland", "Scottish arts festival city", "Lothian city", "Scottish capital", "Scotland's capital", "Auld Reekie" and "'The Athens of the North'".)