Susan goes to unknown location in Egypt (4)
I believe the answer is:
suez
'in egypt' is the definition.
(I know that Suez is part of Egypt)
'susan goes to unknown' is the wordplay.
'susan' becomes 'sue' (short for Susan).
'goes to' is a charade indicator (letters next to each other).
'unknown' becomes 'z' (represents an unknown value in algebra).
'sue'+'z'='SUEZ'
'location' is the link.
I am not very happy about this link. It may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for suez that I've seen before include "African city" , "1956 trouble spot" , "Canal linking Red Sea to Mediterranean" , "Egyptian seaport" , "Middle East canal" .)