Residing in the Mediterranean Sea, Ionian islands signify the passage from the west to the east. A constantly sought-after region due to the trade routes, was for a long time garrisoned and under the authority of the Venetian Republic (fourteenth-eighteenth centuries) that hindered with its fleet the Turkish invasions. The bigger islands that constitute the cluster of the Eptanisa: Corfu, Lefkada or Santa Maura, Ithaka, Kefalonia, Kythira, Zakinthos and more, that had strategic positions with respect to the usual routes, had since the middle ages fortifications like walls, towers and castles, that over the time were expanded and restructured by the Venetians in order to defend those islands from the enemy attacks. The rich iconographic historic material, considering the Ionian Islands, allows to document the characteristics of those wide spread defensive structures and to identify each strong part of this big and unique fortification cluster. It has to be noted that every one of those structures gives us clues about the urban history of the city it resides since they were part of the urban landscape revealing this way the urban layout. The compelling story of the architectural consistency of those fortresses, as it is described in the historic documents, cannot be always verified. Many of those structures are nowadays completely destroyed and only a few remains are left. There are many ways to organize a project for saving those structures and in particular one that will be related with the cultural tourism.