Cosmopoleis in a mirror Alexandria and Seleucia on the Tigris face-to-face

In this essay, documents related to two of the most important cosmopoleis of the Hellenistic world, Alexandria and Seleucia on the Tigris, are examined using comparative analysis to highlight their characteristics.Some features are highlighted in the analysis because of their peculiarity within the panorama of Hellenistic cities: the impact of the foundation of the cities on the landscape – the way land and environ-ment were modified by the establishment of mega-sites; the city layout – the urban development of town planning; the ideological meaning – the way these cities were perceived both at a local and global level. Despite the fact that these two cosmopoleis are accessible through the analysis of documents that appear incoherently comparable, they can nevertheless be seen as cities in a mirror for the similarities they share; however, they also reveal differences that appear related to their local backgrounds.