Concrete message of hope for a possible future of our cities. In the second half of this century, the boundary between town and countryside has been interpreted as a frontier territory to be "civilized" through concrete and asphalt. Buildings, more often unlicensed rather than authorized (at times it is not even clear which are the worst), have thus gradually invaded the countryside, allowing here and there the survival of some little patch of land with elevated value added cultures, within urban expansions degraded by their project. The theme dealt with by the "Saline Ostia Antica" research falls exactly within this kind of issue. The question is: this can cerous building growth absorbing and suffocating nature is absolutely inevitable, or is it possible to transform the boundary between town and countryside into a subsystem capable of integrating the natural with the artificial (or viceversa), foreshadowing a model of sustainable urban development? The challenge accepted by this research is particularly hard, between the impending presence of the past in the nearby ruins of Ostia and a future made of innovative technologies and techniques. The (ambitious) idea regards the proposal of a development project sustainable under both the economical and the ecological point of view, non forgetting the cultural restrictions.