The project aims at sustainable revitalisation of heritage buildings by improving the coexistence of fortified cities and neighbouring forts in urban regions. There is a high number of former fortresses and fortified sites of big historical value in Europe, established in different times. This fortified heritage defines the image of today’s landscape and the struggle and war around these cities define the current borders of municipalities, regions, countries and Europe. But in many cases such constructions are neglected, some derelict, some presented as historical monuments, or only partly utilised. In majority of cases they are fragmented and there is a problem to maintain them as this requires big financial investments and a strong cooperation. The proposed project focuses on a innovative approach by developing smart ways of utilisation of old fortresses. The aim is to make their maintenance easier and to include the fortresses into the life of the City by development of sustainable strategies of the maintenance and exploitation of this heritage. As fortress structures are often viewed from a single point of view, mostly in a conservative way as protected heritage or environment, this project proposes an integrated approach. Both natural and cultural (military) heritage should be adapted and used for current and future challenges.