The Roman overturning of Cuma has hidden the identity of the Greek polis and still influences its perception and any interpretative hypothesis. Contextualizing the historical-archaeological data in the contemporary representations, the prefigurative knowledge of architectural culture reveals symbols and meanings of stories that have been layered by time in the shapes of the landscape. The insular identity of the Cuma-Miseno peninsula mentioned by Strabone comes to light by the semantic and analogical reinterpretation of the archaic Phlegraean geomorphology and suggests the thesis that the Greek polis of Cuma coincided with the whole Phlegraean archipelago. Consolidated over time, this maritime and polycentric polis, when consecrates its foundation as a city-state, 'transfers' its holy and political places in the urban space of Cuma, outpost of archipelago towards the continent («in continentem ausi sedes transferre»). The graphic comparison with Athens leads Cuma among the highest examples of Greek state-cities; it also suggests the location of the archaic-agora into the natural ‘territorial door’ of the Magna Graecia, outlined by the volcanic hills of the Acropolis and the Averno.