Acropolis

An acropolis (Greek: Ακρόπολις; akros, akron, edge, extremity + polis, city; plural: acropoleis or acropolises) is a settlement, especially a citadel, built upon an area of elevated ground—frequently a hill with precipitous sides, chosen for purposes of defense. In many parts of the world, acropoleis became the nuclei of large cities of classical antiquity, such as ancient Rome, which in more recent times grew up on the surrounding lower ground, such as modern Rome.