Urban thresholds. Borders, margins and enclosures

Urban analysis, from its origins, has set up an unfolded approach which, as Leonardo Benévolo explains, is independent from the scale of the city dweller. Major city planning works consider streets, avenues, squares, as structural elements. They make special emphasis on the uniform allocation of public facilities and green spaces, and they keep a homogenous image of their architecture by defining urban patterns… In the end, they work with such globalizing concepts and consider the city a compact and homogenous whole. The approach to this question from a nearer ambit is more sensitive with the notion of urban space as an inhabited space and with its own personality. The criteria of scale, adaptation and transformation, are easier to manage from the pedestrian point of view. Thus, when the building reaches its closer environment, it has the power to transform it, to redefine the city, and this relationship gives way to the true urban space. The street becomes the addition of many little and specific spaces rather than the way to join two separate points in the metropolis. Thus, architecture does not fit in the urban map, quite the opposite, the building constructs the city. The essay herein shall examine examples of previous locations the building uses to modify the urban density and to create a different limit to that of the mere construction. Entering the building or going out to the street is not constricted to the limits of the access door, as Giambattista Nolli proved in his magnificent project of his Dream Rome in 1748.