Caesar's city (4)
I believe the answer is:
rome
'caesar's city' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for rome that I've seen before include "Colosseum city" , "City not built in a day" , "When there, do as the native do" , "All roads lead to it" , "Italian capital (where one Ac died)" .)