"Bro", the Parthenon is a temple. The Acropolis is a citadel.
The Acropolis of Athens (Ancient Greek: ἡ Ἀκρόπολις τῶν Ἀθηνῶν, romanized: hē Akropolis tōn Athēnōn; Modern Greek: Ακρόπολη Αθηνών, romanized: Akrópoli Athinón) is an ancient citadel located on a rocky outcrop above the city of Athens, Greece, and contains the remains of several ancient buildings of great architectural and historical significance, the most famous being the Parthenon.
"Bro", the Parthenon is a temple. The Acropolis is a citadel.
The Acropolis of Athens (Ancient Greek: ἡ Ἀκρόπολις τῶν Ἀθηνῶν, romanized: hē Akropolis tōn Athēnōn; Modern Greek: Ακρόπολη Αθηνών, romanized: Akrópoli Athinón) is an ancient citadel located on a rocky outcrop above the city of Athens, Greece, and contains the remains of several ancient buildings of great architectural and historical significance, the most famous being the Parthenon.
https://en.wikipedia.org/wiki/Acropolis_of_Athens
In fact, that's what "acropolis" (small a) means: it's Greek for "citadel".
And what is a "citadel"?