Car pool is relocated in classical site (9)
I believe the answer is:
acropolis
'classical site' is the definition.
(I've seen this before)
'car pool is relocated' is the wordplay.
'relocated' indicates an anagram.
'car'+'pool'+'is'='carpoolis'
'carpoolis' anagrammed gives 'ACROPOLIS'.
'in' is the link.
(Other definitions for acropolis that I've seen before include "Upper fortified part of Greek city - Athens's is famous" , "Citadel of an ancient Greek town" , "Upper fortified part of Greek city as in Athens" , "Parthenon location" , "old citadel" .)