Carpools I found in an ancient citadel (9)
I believe the answer is:
acropolis
'an ancient citadel' is the definition.
(I've seen this before)
'carpools i found' is the wordplay.
'carpools i' anagrams to 'ACROPOLIS'.
But, I'm unsure how this is indicated.
'in' is the link.
Can you help me to learn more?
(Other definitions for acropolis that I've seen before include "high point" , "Upper fortified part of Greek city - Athens's is famous" , "Imposing building" , "Upper fortified part of Greek city as in Athens" , "old citadel" .)