Stronghold in front of castle with elaborate detail (7)
I believe the answer is:
citadel
'stronghold' is the definition.
(citadel is a kind of stronghold)
'front of castle with elaborate detail' is the wordplay.
'front of' suggests taking the first letters.
'with' means one lot of letters go next to another.
'elaborate' indicates anagramming the letters (I've seen this in other clues).
The first letter of 'castle' is 'c'.
'detail' anagrammed gives 'itadel'.
'c'+'itadel'='CITADEL'
'in' is the link.
(Other definitions for citadel that I've seen before include "Fort, fastness" , "Urban stronghold - dialect (anag)" , "Stronghold (of the Salvation Army?)" , "Stronghold usually within the walls" , "Kremlin" .)