In Brazil, some aspects of the urban reality are not in the official maps. Those aspects are either informal urban elements, built without conventional parameters, or exclusive and exclusionary elements build by a privileged part of society, such as in gated communities. Informal or not, a significant part of these elements does not hold building permits. Furthermore, they are difficult to be represented in maps. The disconnection between the formal and the informal city results in a considerable amount of information that is not represented in official cartography. Thus, the lack of representation of certain urban elements in maps and urban plans is also a socio-spatial segregation symptom. One of the most representative features of Brazilian socio-spatial segregation is the so-called macro urban segregation, in which the higher-class neighborhoods are concentrated in some specific regions, completely separated from the poor communities (VILLAÇA, 2000). This fact explains the reason why the informal settlement areas, like slums, are excluded from many urban zoning plans and formal cartographic representations.

In addition to the irregular settlements, the urban landscape is endowed with smaller scale elements that also generate social exclusion and interfere in the urban and public space, both in material and immaterial ways. Immaterial aspects, such as civility, democracy, and the use of space, are difficult and complex to represent in maps. In turn, the material aspects that cause segregation are not in the maps either. Among the urban reality aspects that are difficult to be mapped, defensive architecture, also named hostile architecture, is the focus of the research work presented here. We consider defensive architecture any construction or object used to control or segregate the urban space, especially the common public space, defining who is allowed to use or access certain areas. Therefore, the elements deployed for this purpose are present in the urban landscape in different forms: protective iron grids, gates, metal spikes, sprinklers, thorn bushes or any other material strategy to control the space.

All these strategies are related to the physical and social segregation of the territory and they assured the use of public space only by some selected groups of people. Nevertheless, the traditional mapping does not follow the fast spread of defensive strategies, making difficult their monitoring and the understanding of their effect on the city. As already mentioned, the architectural elements responsible for exclusionary practices are not registered neither in building permits nor urban plans. Consequently, they are not in any official mapping. Considering that official cartography depicts and represents established policies for the territory occupation – the retrenchment and control to the access and the rights to the territory do not occur only on international borders, the discussion about territorialization, also, implicates excluding or including people within particular boundaries, such as within urban spaces (PETER VANDERGEEST and NANCY LEE PELUSO, 1995).

Motivated by these issues, this research is oriented by how cartography can operate as a spatial analysis instrument to understand the hostile architecture consequences in the public space. Once traditional mapping practices do not include informal elements, such as defensive architecture, our research hypothesis is that the study, classification, and mapping of these elements require diverse arrangements, besides the official ways of representation, such as collaborative mapping and in situ data surveying. The work is in progress and it started in 2017, with the study on the advance of defensive …