The city of Thessaloniki as a synthesis of material and immaterial elements: history, architecture, social and spiritual life. The “historical city” with its transitions: the Ancient city, the Roman, the Byzantine, the Ottoman and, finally, the modern Greek city with its multicultural character. The multiple faces of the city. The transformation of the city through historical events: the fire of 1917, the arrival of refugees in 1922, the annihilation of the Jewish population in 1943. The “modern city”, with its particularities and contradictions, as a living archive, but also as a unique experiential space. Application: From the “imaginary city” to the “real” one, from Italo Calvino’s Invisible Cities to the “visible city”, Thessaloniki. Means of expression: collage, assemblage, maquette. Final synthesis: a collective artwork.