Ophir's case in point as trading place (4)
I believe the answer is:
port
'place' is the definition.
(I know that port is a type of city)
'ophir's case in point' is the wordplay.
'case' suggests removing the centre.
'in' means one lot of letters goes inside another.
'point' becomes 'pt' (abbreviation for point).
'ophir' with its middle taken out is 'or'.
'or' put within 'pt' is 'PORT'.
'as trading' acts as a link.
This may not be correct. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for port that I've seen before include "Wine - left - harbour" , "'Any . . . . In a storm'" , "Wine - shippers use it" , "Harbour; alcoholic drink" , "Popular after dinner liqueur" .)