Mention: The persistence of urban form: interpreting the pre-existences in the construction of the Portuguese city

98 mention Pedro Vasco de Melo Martins The persistence of urban form: Interpreting the pre-existences in the construction of the Portuguese city The persistence of urban form: Interpreting the pre-existences in the construction of the Portuguese city Author Pedro Vasco de Melo Martins Supervisor Sérgio Padrão Fernandes (ULisboa), Co-Supervisor Paulo Jorge Garcia Pereira (ULisboa) University Lisbon School of Architecture, ULisboa (PT) Jury members Professor Giuseppe Strappa (La Sapienza), Professor Jorge Alves Correia (UMin ho), Professor Carlos Dias Coelho (ULisboa), Professor Maria Luísa Trindade (UCoimbra), Professor Rogério Vieira de Almeida (ULis boa), Professor Sérgio Padrão Fernandes (ULisboa) Theme The city and the relationship between built forms and time remains an object of fascination, one of the most emblematic, complex and contradictory human creations, universally seen as a cultural paradigm of eclectic diversity. After the crisis caused by the modern movement, many authors sought to understand the urban object, and especially the comprehension of its formal genesis, that is, analyzing it in search of the elements or rules that lead to its production. However, in the form of the city we find the materialization of an infinity of actions undertaken by multiple individuals and groups, according to cultural and social traditions, economic and technological forces in successive changes. We can therefore 1. Photograph of the Roman Temple of Évora before 1870. Source: Arquivo Histórico da Universidade de Évora, Acervo Túlio Espanca. 12-2025 www.dur.upc.edu The Fifth Manuel de Solà-Morales European Prize 2025 99 consider the urban form as the result of a constant process of construction, maintenance and reuse of countless elements through desires, utopias, accidents and constraints, which over time make the city a heterogeneous and multifaceted entity, a dense and eclectic cultural landscape defined by a particularly complex overlap of built strata, which both preserve and destroy, which both enhance and diminish, which both add and obliterate. Its scale, the countless actors and actions, and its permanent mutation, contribute to the construction of an object with such complexity that it will forever remain virtually impossible to be completely known or understood. The research thus studied the nature of the urban form from the standpoint of its evolution through time, where different urban elements, large and small, partially preserve in their form hidden traces and fragments of the different formal stages that the city evolution once contained. Problematic Given the fundamental role of Time in the construction of the urban form, its study must necessarily imply a diachronic approach to its evolutionary process, that is, its transformation process. However, the study of the evolution of the city’s form, even if focused only on its spatial component, is faced not only with the difficulty of analyzing an object of enormous complexity and time scale, but also and above all with the limitation created by the availability and quality of information about the past city form, which tends to be incomplete, the more so the further back the period of analysis. The knowledge available about the form of the city particularly in earlier periods is largely and with rare exceptions inherently punctual and fragmentary. The loss of information arises as a result of the natural metabolism process of cities in which progress or constant mutation condemns past urban forms, obsolete, worn out by time or simply anachronistic, to be progressively dismantled and totally or partially replaced. The present and future cities are built over the traces of its past, urban evolution is almost always carried out through the destruction or deformation of pre-existing structures, replaced by new elements that will in turn be replaced. However, not all past forms are condemned to destruction, some of these forms have an exceptional resistance to transformation, due to their constructive quality, symbolic value, or even the lack of resources for their dismantling and replacement. These resist the passage of time, leaving their mark on subsequent periods, being successively reused and transformed, or conditioning and structuring the implementation of new forms. The city as a dynamic, mutable and cumulative universe, constantly reinvents itself through the successive superimposition, replacement or recomposition of its pre-existences. At each moment in its history, the form of the city presents a complex mixture of past and present forms that is unique and unrepeatable. Even using information provided by other disciplines, namely History and Archeology, the formal data tends to be fragmentary and incomplete, conditioning the reading of urban evolution. On the other hand, the inscrutable heterogeneity and complexity of urban form can be particularly frustrating for those who study it, particularly given the human appetite for taxonomies that label, compartmentalize and help us understand the apparent chaos of the world around us. We are thus faced with the fundamental problem: in most cases the information necessary to understand past forms is either substantially transformed or even irretrievably lost. If the different urban elements were successively destroyed, built or transformed, 12-2025 www.dur.upc.edu The Fifth Manuel de Solà-Morales European Prize 2025 100 Hypothesis It is, however, in the complex evolutionary process, in itself specific to the urban object, that the key to its understanding lies. The dense construction and reuse of urban structures is comparable to a “palimpsest” 1, in which its pages are systematically reused as support for writing a new text. The city also successively erases and rewrites its structures like words in a palimpsest. And just as the palimpsest hides the fragmentary traces of its original text, revealing a writing hidden beneath the apparent surface, the city also hides within itself the potential to reveal the traces of its past, recoverable through the hermeneutical reading of the urban fabric. Given that the constant transformation of the urban fabric occurs at different rates for different elements, while some are particularly vulnerable to daily transformation, others, such as the urban layout, the plot structure, or certain built structures, are usually stable or particularly resistant, transforming themselves slowly only over long periods of time. These structures, except for major urban restructuring events, tend to preserve their form, or part of it, a “memory” of past forms through processes of fossilization and urban sedimentation. On the other hand, certain urban elements in their genesis obey the formalization of a plan, a concept or an idea (a Type), allowing the interpretation and understanding of their original form even if it has been lost or is substantially deformed, especially through a morpho-typological comparison with other similar structures (Parallels). Therefore, in the search for deepening the understanding of the complex nature of the urban form, this research considers the central hypothesis that this knowledge can only be achieved through the study urban form’s whole, global, evolutionary process, in comparison and dialogue with other similar forms. 1 Giovannoni, Vecchie cittá ed edilizia nuova. The research thus considered that hypothetically, despite in inherently fragmented and incomplete information on this evolutionary process, a hermeneutic reading of the current urban fabric together with a typo-morphological comparison of the remains has the potential to reveal the past shapes that once defined the urban layout, and through this analysis achieve a deeper meaning on the nature of the urban form. In complement the research also tried to test the viability of understanding urban forms as a typological object, whose history and various structures, such as buildings, streets, layouts and other elements, share important common features with other forms inserted in the same cultural context. This hypothesis allows, in theory, to apply existing knowledge about certain aspects of the evolution of certain structures to others that share the same cultural framework, thus completing their evolution. Reading the evolution of urban form according to a common cultural framework also allows us to affirm the hypothesis that it is possible to verify the existence of structuring phenomena that are transversal to eras and cultures, as well as others that, on the other hand, can be exclusive to certain periods or spaces. That is: some act within the scope of conformity to pre-existences, that function as a previous “norm”; while others carry out a more radical process of transformation, but even so, revealing traces of the pre-existences on which (and sometimes against which) they act – seeking to create a new norm. Objectives At a time when the unsustainability of indefinite and unlimited urban expansion is apparent, the creation of instruments that allow us to study and understand of the existing city is increasingly important. These instruments make it possible to carry out more conscious and informed interventions, which, when considering the role of pre-existences in the construction of urban form, are 12-2025 www.dur.upc.edu The Fifth Manuel de Solà-Morales European Prize 2025 101 capable of putting the past (history), present and future (in the development of projects) into dialogue. In the search for an understanding of the urban form, this investigation considered that this can and should be achieved mainly through the study of its complete and global evolutionary process. Therefore, the research’s underlying objective was to improve our understanding of the nature of the urban form, considering that the urban evolution over time results from a continuous act of fabric production on pre-existences that leave their mark on subsequent structures that are imposed or adapted to them. To achieve this the research had as a main objective the formal reconstruction of the evolutionary process of several Portuguese cities, having in mind the possibility of producing comparative readings, either in time (comparing the different evolution phases of a particular city), as well as in space (comparing the layout of different cities in a specific time period). Complementarily the research also had as a goal the creation of a methodology that allowed the efficient analysis of large amounts of information, crossing different sources, and from them facilitated the reconstruction of the main evolution phases of each city. Methodology The applied methodology was based on a hermeneutic reading of the city’s built forms, understanding that deeper knowledge from the city built depends on studying the form of each individual part, as well as understanding how each of these autonomous parts articulates itself with the whole. This hermeneutic reading should extend beyond the current form of the contemporary city and its constituent parts, to the study of its evolutionary process through successive conceptual phases that gradually contribute to generating the current form. To overcome the incomplete nature of the information available for the past urban forms the research methodologically approached this problem from an inductive perspective, presupposing the reconstruction of the missing information in the analysed forms based on the identification of their compositional principles (Type). These can only be achieved from the direct comparison similar shapes (Parallels), that is through a typo-morphological comparison. Only from the comprehension of these composition rules can an inductive hypothetical reconstruction be achieved. This perspective that starts from the composition rules of a number of particular cases to conclude a general rule, which can thus be used to reconstruct other cases; to a certain extent, is methodologically similar to the approach that structuralism proposes for understanding cultural structures. This approach, initially applied to Linguistics, by Ferdinand de Saussure (1857-1913), was later and theoretically expanded to apply to the analysis of all cultural productions (literary works, musical or performative works, the plastic arts). According to the structuralist conception (which we apply here, but limiting ourselves to its first, Saussuraian iteration) all human cultural productions are framed or shaped by conceptual structures, this being the case for example, for literary works that can be structured according to genres. This conception based on compositional/structuring principles – or rules of composition – follows, in our view and for our purposes in methodological terms, the concept of Type or Architectural Typology, corresponding to the conceptual structures that, according to structuralism, shape creation of works in culture. The methodology we applied – although not exclusively – therefore uses the comparison of buildings with relevant parallels, models, Types and Stereotypes, which are part of the same cultural context, as a fundamental step towards reconstructing the evolution of architectural and urban forms. The typo-morphological comparison (which we consider here as Saussurian syntagmas) with other 12-2025 www.dur.upc.edu The Fifth Manuel de Solà-Morales European Prize 2025 102 over time, that is, to a diachronic reading; the second axis, the axis of simultaneous events, refers to their study at a specific moment in time, that is, to a synchronic reading 2. The research used these concepts as the methodological basis for the study of constructed forms, through the conceptual construction of a coordinates matrix, with two axes X and Y, in which the variables of Time (Diachrony) and Space (Synchrony) are represented. This analytical device created an effective tool for the proposed comparative readings to be carried out, on one axis, evaluating the evolution of the forms of a city over time (Diachrony); or on the other axis, comparing various urban forms from a specific period (Synchrony) Therefore, comparative readings serve a privileged role in the research, as a fundamental element of the analysis and recon2 Waterman, “Ferdinand de Saussure-Forerunner of Modern Structuralism” The Modern Language Journal, 307-309. contexts thus assumed vital importance in the analysis, not only because it allows missing information to be reconstructed, but also because it is possible through a comparative reading (with the paradigm at hand) to highlight common or singular characteristics in the development of forms. Structuralism also offered for this research another relevant perspective through the use of two fundamental concepts in linguistic analysis: Diachrony and Synchrony. Within the scope of linguistics, Diachrony considers the study of language through time, its history, that is, its progressive transformation or evolution, while Synchrony focuses on the study of the “closed” language at a given moment, without considering the historical reasons behind its structure. These two concepts are transformed into two Cartesian axes: the axis of successive events and the axis of simultaneous events. The first axis, the axis of successive events, refers to the study of the evolution of a language 2. Reconstruction of Diocletian’s palace in Split. Source: Adam Caruso, ETH Zürich Studio, https://caruso.arch.ethz.ch/project/202. 12-2025 www.dur.upc.edu The Fifth Manuel de Solà-Morales European Prize 2025 103 3. Adaptation of the Structuralist approach to urban evolution. Source: Author struction of past forms, through the comparison between the past and the present, or through the comparison between similar, complete and incomplete forms existing in different contexts (e.g. different cities). On the other hand, these methodologies not only offer fundamental elements for reconstructing incomplete forms, but also allow for a privileged assessment of the transformations and permanence of different urban spaces or built forms according to a global perspective that considers the urban form as a whole and the of its evolution in time and space. Delimitation of the Theme in Space and Time In order to achieve the proposed objectives the research realized a comprehensive reading of three urban centers, understanding them as part of a vast interconnected system, which would allow, through comparative readings, to evaluate their evolution, mutation and development, understanding which singular or common features characterized their evolution. In other words, an analysis went beyond the limits and particularities of each urban agglomeration, to a global perspective of several Portuguese cities through various historical periods. The research thus focused on the cities of Braga, Coimbra and Évora, considering that these cities, of comparable scale and importance, are representative of both a comprehensive geographical distribution between the North, Center and South of the country, as well as a comprehensive chronological distribution from a pre-roman (pre-urban) period to the present day, making them ideal for comparative readings. In order to facilitate the comparative readings the chronological evolution of these cities was condensed in to 14 distinct time intervals: Phase 1 - before the 1st century BC; Phase 2 - between the 1st 12-2025 www.dur.upc.edu The Fifth Manuel de Solà-Morales European Prize 2025 104 century BC and the 1st century; Phase 3 - between the 1st and 4th centuries; Phase 4 - between the 4th and 8th centuries; Phase 5 - between the 8th and 12th centuries; Phase 6 - 12th century; Phase 7 - 13th century; Phase 8 - 14th century; Phase 9 - 15th century; Phase 10 - 16th century; Phase 11 - 17th century; Phase 12 - 18th century; Phase 13 - 19th century; and Phase 14 - 20th century. Given the lesser information, phases 1, 2, 3, 4 and 5 condense longer time intervals, from phase 6 onwards the availability of information allows each phase to span a period of a century. The time scale was taken as an interval of a century for the phases that fall between phase 6 and phase 14, since this interval allows for relative coverage and, above all, establishes a common unit of time as well as also comparable to criteria consensually established by History. For the formal analysis and reconstruction of the urban layouts in the different time periods, the research considered an area corresponding to a square of 2000 by 2000 meters, that is, 400 hectares. The determination of this analysis surface, relatively arbitrary, results mainly from the observation that it would represent the vast majority of interventions carried out over the centuries, with the exception, of course, for the explosion of urban perimeters that occurred mainly in the second half of the 20th century. On the other hand, the choice of this area also responds to determinations of scale and readability of the work, seeking to ensure that the information collected is understood - and seen - in the context and limits imposed by the format determined for a doctoral dissertation. The various plans of the different cities represent the same urban components (topography, urban layout, common buildings and singular buildings), using common design criteria (the same orientation, the same scale, line thickness, etc..), thus allowing comparison directly between the case studies. Given the focus of the research is on the evolution and dynamic perception of urban form, each scheme Braga Coimbra Évora 4. Case Study distribution. Source: Author 12-2025 www.dur.upc.edu The Fifth Manuel de Solà-Morales European Prize 2025 105 represents a time interval, and not a static moment in the city’s evolution, recording the transformations that occurred in each period. Thus, to represent the dynamism of the urban evolution elements are represented using three different color codes: consolidated stable elements in black; elements in construction in red; and abandoned in dissolution or demolition elements in gray. Structure and Organization of the Dissertation The work was structured into three essential moments: “Reading the form” describing the methodologies and sources necessary for the analysis; the “Evolution of form”, where the methodologies previously described are applied in the analysis of three cities; and the “Final considerations” where the main conclusions of the research are presented. The first moment, “Reading the form”, focuses on the difficulty of morphological analysis of sedimented urban fabrics, given their extreme complexity and overlap. Thus, in a first moment, the different perspectives published to date and containing various interpretations related to the theme of this dissertation are addressed, highlighting their methodologies and contributions. From the perspectives presented by different disciplines, the research proposed reading the urban form and interpreting the fragmentary evidence of its past forms through three fundamental sources of information: The “historical framework”, the “analysis of the urban fabric” and the “typo-morphological comparison”. The “historical framework” presupposes the collection of all existing information on the urban forms through the survey of textual descriptions, graphic representations as well as the most recent theoretical-practical research works (such as archeology). These pieces of information offer fundamental perspectives on the built structures, either through their recording at key moments or through their subsequent historical-archaeological interpretation by other 5. Coimbra between the 8th and 12th centuries. Source: Author 12-2025 www.dur.upc.edu The Fifth Manuel de Solà-Morales European Prize 2025 106 a relatively unique evolution. If in Braga the city’s development is characterized by linear growth along the streets, in Coimbra we see growth resulting from the densification and ruralization of Alta and Baixa, while in Évora we witness a tendency towards the systematic addition of new planned urban spaces. Thus, the initial premise that also sought to understand urban forms from a type-morphological point of view has a limited application - but necessarily attempted to confront hypotheses - in the case studies analyzed. In the last moment, “final considerations”, more than a global synthesis of the research, it establishes a reflective thinking on the theme of the resistance of urban forms: what are the main questions that the research managed to answer, and to what extent other questions remained unknown. This final chapter also presented the main contributions of this work to understanding of the evolution of built forms in the analyzed cities as well as in the broader perspective of the Portuguese city. Complementary this chapter also points out future directions for the development of new lines of research opened by this work. Key results / Final considerations Given the complexity and singularity of urban forms, the question that arose at the start of the research was whether it was possible to carry out an operational reading of the complete progressive transformation and evolution of a specific urban context, presupposing an ambitious analysis that would enable the reconstruction of the evolutionary process. The initial answer to this fundamental question is positive, as the application of the proposed methodology allowed for the effective reconstruction of the complete formal evolution of three cities, from their initial hypothetical moment to the present day, registering in 14 phases every notable transformation of the shape of their specific components (buildings, streets, city walls, etc…). authors. The “analysis of the urban fabric” corresponds to the systemic disassembly of the fabric into four elementary systems: layout, parcel, buildings and topography. The complexity of the forms is thus condensed into their fundamental aspects, meaning that structures and processes which otherwise would be diluted over the complexity of the urban fabric are instead clearly presented, making them simpler, more perceptible and more evident. Finaly the “typo-morphological comparison” addresses the problem of theoretical reconstruction of past forms. These are in most cases partially preserved. However, through comparison with similar structures, it is possible to interpret or restore the original nature of the incomplete elements of the cases under study. This comparison is carried out through the elaboration of a schematic simplification of the form, that is, establishing a theoretical model based on constructed typologies that synthesizes and compartmentalizes the morphological complexities of urban structures into their formal invariants. The second moment, dedicated to the “Evolution of form” addresses, based on the methodologies and sources of information established in the previous chapter, the evolution of the three chosen Portuguese cities, from the pre roman period to the present. The analysis of these cities was carried out in a relatively autonomous way for each city, always having as its final objective the possibility of carrying out transversal readings, between different spaces and different times. The urban object was also considered as having a typological potential, that from a comparative reading could result in the elimination of gaps in the information on its historical process, using relatively well-documented periods in a context, to explain other contexts for which information was excessively fragmentary or non-existent. However, the final reading of the document demonstrates the limitations of this vision, as the comparison of the development of the cities of Braga, Coimbra and Évora demonstrated how each of the three centers has 12-2025 www.dur.upc.edu The Fifth Manuel de Solà-Morales European Prize 2025