Like every other capital

of a pre-unified Italian state, Venice expanded beyond its walls during the modern era. If the city is a projection of the community that inhabits it, then it is the civitas, the city of the people, that delineates the real functional boundaries of Venice, surpassing the material limits of the walls and buildings (urbs). Today, the Venetian civitas is expressed through the interaction of nearly a million individuals, involving both lagoon settlements and mainland settlements within a single functional area. The Venetian uniqueness is given by the lagoon, the walls of Venice, which sometimes act as a connector and sometimes as an obstacle to the flow of interaction between the different parts. The ability to measure these flows across a large area is essential for their sustainable management.