City left men inside barrier (8)
I believe the answer is:
florence
'city' is the definition.
(Florence is an example)
'left men inside barrier' is the wordplay.
'left' becomes 'l' (common abbreviation).
'men' becomes 'or' (I've seen this in other clues).
'inside' means one lot of letters goes inside another.
'barrier' becomes 'fence' (fence is a kind of barrier**).
'l'+'or'='lor'
'lor' placed within 'fence' is 'FLORENCE'.
(Other definitions for florence that I've seen before include "Italian city, noted art centre" , "Italian city; Magic Roundabout character" , "foreign city" , "Nurse Nightingale in Italian city" , "Nightingale possibly" .)