Visiting The Archaeological Site of Pella. The site of Pella is a journey to the heart of the ancient city, the capital of Macedonia from the late 5th century BC, when it was transferred from Aigai, because of it's proximity to the sea and trade routes of north. Pella was organized and expanded during the reign of Philip ll, become the mother city of Alexander the Great and reached its heyday in the Hellenistic period, namely during the reign of Cassandra and Antigonos Gonatas.