The Roman houses of Tongobriga: architecture and cultural change^*This paper was produced in the framework of the Lab2PT- Landscape, Heritage and Territory Laboratory through the project UID/AUR/04509/2013, funded by POCI-01-0145-FEDER-007528.

1. INTRODUCTION

In the second half of the 20^th century, domestic architecture began being used by both anthropologists and ethnologists in their study of the social relationships amongst pre-industrial communities. In this context, Claude Lévi-Strauss (1987)Lévi-Strauss, C. 1987: Anthropology and Myth: Lectures 1951-1982. Blackwell, Oxford., based on kinship studies, developed the concept of “sociétés à maison”, in which the house was at the core centre of the social organisation. This same interpretation was later adapted to archaeology through the pioneering work of Kent Flannery (Flannery and Winter 1976Flannery, K. and Winter, M. 1976: “Analysing household activities”, in K. Flannery (ed.), The Early Mesoamerican Village, pp. 34-44. Academic Press, New York.). To the contribution of those authors were added the studies of Amos Rapoport (1969Rapoport, A. 1969: House form and Culture. University College, London., 1990)Rapoport, A. 1990: The Meaning of the Built Environment: A Nonverbal Communication Approach. University of Arizona Press, Tucson. and those of sociologist Pierre Bourdieu (1977)Bourdieu, P. 1977: Outline of a Theory of Practice. R. Nice (trans.). Cambridge University Press, Cambridge.. In another study (1970Bourdieu, P. 1970: “La maison Kabyle ou le monde renversé”, in J. Pouillon and P. Maranda (eds), Échanges et Communications: Mélanges offerte à Claude Lévi-Strauss, II, pp. 739-758. Paris.), focusing on the architecture and distribution of objects around the traditional Berber house in northern Algeria (Cabília), developed the idea of habitus as a way to express the collective behaviour that existed between the everyday life and the trivial. Under these circumstances, the domestic routines of pre-industrial societies came to be considered an expression of social attitudes. In this same way, the study of the traditional housing unit ended up becoming a powerful analytical tool in the overall understanding of communities’ social structures.

In the 1970s, American archaeology, in close articulation with anthropology, adopted anthropological and sociological analyses that were systematically applied to the study of the domestic organisation of ancient societies in the American continent. In some cases, as for example the Mayans of Yucatán, Guatemala and Belize, there were still contemporary settlements built by the descendants of the ancient Mayans, which, in turn, allowed comparisons to be made between ancient and present-day domestic habitus. If Archaeology centred around the results of excavations, Ethnohistory was concerned with comparison analyses. The work of Richard Wilk and William Rathje in 1982Wilk, R. and Rathje, W. 1982: “Household archaeology”, American Behavioral Scientist, 25 (6), pp. 617-639. https://doi.org/10.1177/000276482025006003 , entitled “household archaeology”, summarised with great clarity the steps that followed the development of a real “prehistory of domestic life”.

At the end of the 20^th century, the first anthropological studies on houses and domestic structures emerged, and focused around the pre-industrial societies of all regions (Blanton 1994Blanton, R. 1994: Houses and Households: A Comparative Study, Interdisciplinary Contributions to Archaeology. Plenum Press, London and New York.). The use of diffused diagrams to study the connectivity existing between the spaces of a house and their respective chronologies, including prehistory, was carried out (Hendon 1996Hendon, J. 1996: “Archaeological Approaches to the Organization of Domestic Labor: Household Practice and Domestic Relations”, Annual Review of Anthropology, 25, pp. 45-61.). Researchers analysed the distribution of objects recovered from excavations, aimed at then interpreting the domestic units. In this same period, the study of the classical world’s domestic life started including an anthropological approach from authors as L. Nevett (1992)Nevett, L. 1992: Variation in the Form and Use of Domestic Space in the Greek World in the Classical and Hellenistic Periods, Ph.D. thesis, University of Cambridge. Cambridge., who carried out an analysis of the Hellenistic houses, also applied to the Roman world. In reality, the new interpretative paradigm would later be adopted to explore the rich archaeological documentation accumulated in over 200 years of excavations conducted in Pompeii and Herculaneum. This can finally be explored via alternative and complementary methodological lines expressed in, for example, the ground-breaking study of objects and artefacts developed by P. M. Allison (1992Allison, P. 1992: The Distribution of Pompeian House Contents and its Significance, Ph.D. thesis, University of Sydney. University Microfilms International, Ann Arbor., 1997)Allison, P. 1997: “Artefact Distribution and Spatial Function in Pompeian Houses”, in B. Rawson and P. Weaver (eds.), The Roman Family in Italy: Status, Sentiment, Space, pp. 321-354. Clarendon Press, Oxford., or in the study of architecture and decoration of houses conducted by A. Wallace-Hadrill (1994)Wallace-Hadrill, A. 1994: Houses and Society in Pompeii and Herculaneum. Princeton University Press, Princeton. and R. Laurence (1994Laurence, R. 1994: Roman Pompeii: Space and Society. Routledge, London., 1997)Laurence, R. 1997: “Space and Text”, in R. Laurence and A. Wallace-Hadrill (eds.), Domestic Space in the Roman World: Pompeii and Beyond, Journal of Roman Archaeology Supplement, 22, pp. 7-14. Portsmouth.. Due to its remarkable state of conservation, the architecture of the houses in Pompeii and Herculaneum came to represent a fundamental interpretive context for analysing the social life of the Roman society, and consequentially inspired wider architectural studies conducted in other provincial towns.

This is the base we aim to follow when analysing a group of excavated houses included in a residential neighbourhood of the Roman city of Tongobriga, located in northern Portugal, and performing a city that was part of the Bracaraugustanus conventus, in the Tarraconensis province. To this end, a spatial and architectural assessment of the buildings was carried out, with a view to interpret it from an anthropological standpoint and better understand the new social ways that developed among the indigenous populations inhabiting the northwest Iberian Peninsula, and who came to adopt the housing models of italic origin.

Based on available archaeological data, it was possible to reconstruct the floor plan and the second floor of Tongobriga’s Roman houses. Their morphology was influenced by both external and internal access features, and therefore the articulating elements in the houses were valued. An emphasis was given towards open spaces, such as atria, peristyla and courtyards, with a morphology that shaped the distribution of the remaining areas and influenced the location of staircases connecting to the upper rooms. Equally relevant was the relationship existing between the house and the outside world, in addition to the location of streets and of other circulation elements, such as porches. Taking advantage of data concerning the Roman living space of Tongobriga, it was possible to improve our understanding on the features of Roman residential architecture in the northwest territory of the Iberian Peninsula and to assess its wide compositional versatility that questions the existence of imported and faithfully recreated typologies and models (Magalhães 2019Magalhães, M. 2019: A domus Romana no Noroeste Peninsular: Construção, Arquitetura e Sociabilidades, Ph.D. thesis. Universidade do Minho, Braga.). The conducted analysis and the comparison of the new Roman constructions with the “Castreja culture” houses from the late Iron Age, as for example the well-known indigenous settlement of Citânia de Briteiros (Magalhães 2019Magalhães, M. 2019: A domus Romana no Noroeste Peninsular: Construção, Arquitetura e Sociabilidades, Ph.D. thesis. Universidade do Minho, Braga.), shed some light on the habitus concept put forward by Bordieu (1977)Bourdieu, P. 1977: Outline of a Theory of Practice. R. Nice (trans.). Cambridge University Press, Cambridge., and stressed its significance as an indicator of both cultural and social change occurring between the end of the 1^st century BC and the middle of the 2^nd century, more specifically between the reign of Augustus and the end of Hadrian’s era.

2. THE HISTORICAL AND CULTURAL CONTEXTS: ROMAN URBANISATION IN THE NORTHWEST IBERIAN PENINSULA

The Roman victory over the heterogeneous territories integrated into the Roman province of Hispania Tarraconensis took place between the end of the 3^rd century and the end of the 1^st BC. It coincided with the gradual annexation of the regions bordering the western and northern part of the Iberian Peninsula. The later integration of the north-western region in the Empire deserves some attention. We are aware that it was finalised in the Augustan era, at the end of the Cantabrian Wars, from the year 19 BC onwards. However, the area corresponding to the territory stretching between the Douro and the Minho rivers entered the orbit of the Roman world in 137 BC, following on the expedition of Decimus Iunius Brutus (Tranoy 1981Tranoy, A. 1981: La Galice Romaine. Recherches sur le Nord-Ouest de la Peninsule Ibérique. Diffusion de Boccard, Paris.; Martins et al. 2018Martins, M., Magalhães, F. and Botica, N. 2018: “O urbanismo fundacional de Bracara Augusta e Lucus Augusti”, in D. Dopico Caínzos and M. Villanueva Acuña (eds.), Atas do Coloquio Internacional Sine Iniuria in paca Vivatur: La construcción del Imperio durantes los julio-claudios (Lugo, 2017), pp. 345-373. Deputación de Lugo, Lugo). Still, the integration of the north-western part of the Iberian Peninsula into the Roman administration was intimately associated with the administrative reorganisation of Hispania undertaken by Augustus, and with the creation of new provinces and cities gifted with both social and political structures that underlined the consolidation of the Roman presence in the region and facilitated the integration of the indigenous populations living in this heterogeneous land (Villanueva 2016Villanueva Acuña, M. 2016: “La fundación de Lucus Augusti: nuevas perspectivas”, Revista de Historiografía, 25, pp. 273-286. https://doi.org/10.20318/revhisto.2017.3586 ). The region was a polymorphic ethnic, cultural and socioeconomic reality; it included areas that were much closer to the Mediterranean cultural inflows, as for example the southernmost region, and others that remained marginal to these influences, located more towards the north and the inner lands (González 2006-2007Gonzalez Ruibal, A. 2006-2007: Galaicos. Poder y Comunidad en el Noroeste de la Península Ibérica (1200 a.C.-50 d.C.), Brigantium, 18-19. Museo Arqueológico e Histórico da Coruña, A Coruña.).

In order to understand the nature of the cultural and social changes that took place within the indigenous groups throughout the 1^st century, as a result of their integration into the Roman administrative and economic system, it was important to analyse the specificity of the different regions in the Iberian Peninsula, which offered different realities in light of archaeological data provided by research (Fig. 1).

One of the best-known north-western Iberian sub-regions corresponded to the area between the Minho and Douro rivers, which has been the object of several studies, either in terms of settlement archaeology or in its analyses of specific cities. Among these, the works focused on the urbanism and architecture of Bracara Augusta should be mentioned. This is a city founded in the time of Augustus, around the year 15 BC, and it was the capital of the bracaraugustanus conventus (Martins and Carvalho 2017Martins, M. and Carvalho, H. 2017: “The Roman city of Bracara Augusta (Hispania Citerior Tarraconensis): urbanism and territory occupation”, Agri Centuriati. An International Journal of Landscape Archaeology, 14, pp. 79-86.). There was also archaeological and epigraphic data related to the city of Aqua Flaviae. It acquired great prominence in the Trajan period, when the bridge over the Tâmega river was built in the year 104, under the initiative of the Aquaflavians, as it can be interpreted from the text engraved in a column recovered from the river in 1980 (Ribeiro 2010: 65-66Ribeiro, J. 2010: O tecido urbano flaviense: de Aquae Flaviae a Chaves Medieval, Ms. Dissertation. Universidade do Minho, Braga.). The city was located on the axis of the Roman road XVII connecting Bracara Augusta to Asturica Augusta, and probably functioned as the regional capital of a group of people also mentioned in this same column, alongside Padrão dos Povos that can also be found at the bridge (Martins et al. 2005Martins, M., Lemos, F. and Pérez Losada, F. 2005: “O Povoamento Romano no Território dos Galaicos Bracarenses”, in C. Fernández Ochoa and P. García Díaz (eds.), Unidade y Diversidad en el Arco Atlântico en Época Romana, III Colóquio Internacional de Arqueologia en Gijón (Gijón, 2002), BAR International Series 1371, pp. 279-296. Archaeopress/Ayuntamiento de Gijón, Oxford.; Carvalho 2008Carvalho, H. 2008: O Povoamento romano na fachada ocidental do Conventus Bracarensis, Ph.D. thesis. Universidade do Minho, Braga.). Another Roman city located in the bracaraugustanus conventus that has been the object of extensive excavation works is Tongobriga, which evolved from an indigenous settlement (Dias 1997Dias, L. 1997: Tongobriga. IPPAR, Lisbon.). Despite the scarcity of available data related to the old pre-Roman settlement, we know that the original houses had a circular plan that still exists today under part of the excavated houses assembling the small Roman housing group on site. The identified pre-Roman dwellings seem to be organised around residential sets, a common feature also present in the wide settlements from the second Iron Age period in the western part of the bracaraugustan Gallaecian region. Another common feature of the wide oppida-type settlements was their large size, which should have had about 13 hectares, an estimated dimension interpreted from aerial photography and from the layout of the walled perimeter, defined by a fortification acknowledged from the segments that displayed the typical features of the north-western castros in the Iberian Peninsula (González 2006-2007Gonzalez Ruibal, A. 2006-2007: Galaicos. Poder y Comunidad en el Noroeste de la Península Ibérica (1200 a.C.-50 d.C.), Brigantium, 18-19. Museo Arqueológico e Histórico da Coruña, A Coruña.). Adding to this, the existence of an indigenous bathing structure, of the ‘pedra formosa’ type, located next to the southwestern part of the wall, was another oppida common feature in the Bracaraugustan Gallaecian region. They were mainly built after the Decimus Junius Brutus military campaign, between 138/136 BC. Adding to this, they have been associated with the reorganisation and hierarchisation of the population, and some of these settlements can be considered as true indigenous towns due to their political, economic and religious functions, alongside the centrality they had in regional terms. They normally occupied prominent positions within the landscape, and exhibited an optimal visual control over the surrounding territory. We believe that the pre-Roman settlement of Tongobriga corresponded to an oppidum, which would have had circulation axes that organised the neighbourhoods and the domestic units in them. They were bounded by walls and had several buildings unified by paved yards, which was a type of organisation in line with these types of sites. It seemed therefore acceptable that the Roman occupation gave the site’s pre-Roman nucleus a natural continuity, enabling it to inherit the singular centrality already in place. This type of settlement was also prone to house ritual and religious activities, which saw the seasonal concentration of regional populations. The “Castreja culture” bathing structures, which have only ever been identified in large oppida-type sites, as in Briteiros or Sanfins, likely provided the architectural contexts to perform some of these rituals (Silva and Machado 2007Silva, A. and Machado, J. 2007: “Banhos Castrejos do Norte de Portugal”, in Silva, A. (coord.), Pedra Formosa ‒ Arqueologia Experimental, pp. 20-60. Câmara Municipal de Vila Nova de Famalicão/Museu Nacional de Arqueologia, Vila Nova de Famalicão.; Lemos et al. 2008Lemos, F., Cruz, G. and Fonte, J. 2008: “Estruturas de banhos do território do Bracari: os casos de Briteiros e de Braga”, en I Congreso internacional de Arqueoloxía de Vilalba, Fervédes, 5, pp. 319-328. Museo de Prehistoria e Arqueoloxía de Vilalba, Vilalba.).

Under these circumstances, the Roman city of Tongobriga, seems to result from the evolution of an indigenous cluster. It saw its population being gradually acculturated, whilst adopting new residential structures, alongside new daily habits that included the use of new spaces, as for example the bathing structures, in addition to being introduced to new religious and funeral rituals that the indigenous communities ended up adopting. This adaptation process took place between the Augustan period and the Flavian dynasty, at a time that was marked by the Vespasian’s attribution of Latin law to the inhabitants of Hispania, a circumstance that allowed the reinforcement of the process of cultural integration within the north-west Iberian region. It also favoured the promotion of some clusters of indigenous origin. A note should also be given to the development of several urban centres located in strategic areas from an economic and transportation point-of-view, some of which came to know relevant urban and architectural programs that documented the evolution of the territories and the economic and cultural changes operated in them (Martins et al. 2005Martins, M., Lemos, F. and Pérez Losada, F. 2005: “O Povoamento Romano no Território dos Galaicos Bracarenses”, in C. Fernández Ochoa and P. García Díaz (eds.), Unidade y Diversidad en el Arco Atlântico en Época Romana, III Colóquio Internacional de Arqueologia en Gijón (Gijón, 2002), BAR International Series 1371, pp. 279-296. Archaeopress/Ayuntamiento de Gijón, Oxford.). This seems to have been the case with Tongobriga, where the well-known Roman spaces and buildings generally dated from the end of the 1^st century, although it is admissible the existence of Roman-type buildings preceding the monumentalization of the space. This process included the construction of a public bathing structure and a large square, believed to have been the forum (Rocha et al. 2014Rocha, C., Dias, L. and Alarcão, P. 2014: Tongobriga. Reflexões sobre o seu desenho urbano. CITCEM/Edições Afrontamento, Porto.) (Fig. 2).

Located on the southern border of the bracaraugustanus conventus, the urban settlement of Tongobriga inherited the pre-Latin name of the Iron Age indigenous site. It also seemed to have fulfilled geostrategic functions in terms of playing a role in organising the territory, being also possible that its prominent regional status arose from the centrality that the site would have already had in pre-Roman times. It was associated with the control over two important peninsular routes, one of them being the Douro river and the other the road connecting Bracara Augusta to Augusta Emerita, although this road was just a set of independent pathways covering a very rugged territory (Carvalho 2008Carvalho, H. 2008: O Povoamento romano na fachada ocidental do Conventus Bracarensis, Ph.D. thesis. Universidade do Minho, Braga.).

Little is known about the evolution of Tongobriga until the end of the 1^st century. It is plausible to assume that some structures of Roman origin may have been gradually introduced. At the same time, the centrality of the populational nucleus, deriving from its privileged location, likely attracted both people and services. This justified its continued populational growth and was the reason behind the construction of a public baths building in the 2^nd century, at the exact site where the previous bathhouse was located. A large square was also attached to it (Dias 1997Dias, L. 1997: Tongobriga. IPPAR, Lisbon.). Some of the original Roman structures may have been camouflaged by the monumental character given to the space during the Antonine era, as it happened to the known housing areas that underwent a profound reorganisation with the installation of italic type residences. These adapted in a more or less organic way to the rugged topography of the land, and therefore replaced the circular houses of indigenous tradition.

The occupation of the Roman Tongobriga was hypothetically discontinued at the end of the 7^th century. The city was referred to as Tongobria in the so-called ‘Parochiale Suevorum’, dating from the second half of the 6^th century, a manuscript also known as Divisio Theodemiri. This performs a remarkable historiographic document that accounts for the organisation of a post-Roman Galicia. All 134 parishes were identified and grouped around 13 dioceses (David 1947David, P. 1947: Études historiques sur la Galice et le Portugal du VIe au XIIe siècle, Collection Portuguaise, 7. Les Belles Lettres, Lisbon/Paris.). A building from the end of the 4^th century/beginning of the 5^th, with floors covered in polychrome mosaics, and identified in the churchyard excavations conducted at the church of Santa Maria do Freixo, was adapted to cult practices between the 5^th/6^th centuries, and seemed to correspond to a paleo-Christian basilica, perhaps the ecclesia of the Swabian parish (Rocha et al. 2014Rocha, C., Dias, L. and Alarcão, P. 2014: Tongobriga. Reflexões sobre o seu desenho urbano. CITCEM/Edições Afrontamento, Porto.). The Roman and late-antique settlement of Tongobriga, presumably abandoned at the end of the 7^th century, was succeeded by a Christian parish at the end of the 9^th century/beginning of the 10^th, known as Santa Maria do Freixo, which is still the name of the present-day village.

In 1882, a votive altar dedicated to Genio Tongobricensium (CIL II 5564) was discovered and that made it possible to establish a relationship between the Freixo site and the Swabian parish from the end of the 6^th century. This was the name that was then given to the place where, since the 18^th century, several ruins have gradually been uncovered. However, archaeological excavations at the Tongobriga site only really began in 1980, in a place known as ‘Capela dos Mouros’ (Moorish Chapel), where the Roman baths were to be identified. Since then, several archaeological seasons have spread over a wide area with around three dozen hectares, which has then allowed the delimitation of the archaeological site. It includes the proto-historical settlement and an area with structures with Roman chronology, known as the civic centre and consisting of public baths and a large rectangular square. To the south of this last set there is a necropolis area. All archaeological works on site have been developed as part of a permanent research project, which is today under the radar of the Northern Regional Directorate for Culture (Dias 1997Dias, L. 1997: Tongobriga. IPPAR, Lisbon.; Rocha et al. 2014Rocha, C., Dias, L. and Alarcão, P. 2014: Tongobriga. Reflexões sobre o seu desenho urbano. CITCEM/Edições Afrontamento, Porto.).

At the end of the 1^st century, the “Castreja culture” baths were replaced by a thermal complex redesigned at the end of the 2^nd century to widen the bathing area. From this period is also the construction of a natatio that occupied the central part of the previous palaestra and was surrounded by a 12-column portico. Attached to this area and to the west, there was an apodyterium, through which one could enter the baths that had, at this point in time, a bigger number of rooms. In the first half of the 2^nd century, a large square was also built. It has been classified as the forum and performed an area of about 10,000 m², 149 m long (E/W direction) by 68.5 m wide. Whatever the function this space had, we are dealing with an extraordinary example of the processes that involved the indigenous populations from the peninsular northwest, who saw their integration into the Roman cultural system.

The cultural changes associated with the inclusion of indigenous populations into the Roman world can also be visible in the residential areas uncovered in the excavations of two housing units, one on the western slope, located next to the current church and the other on the eastern slope, right next to a wall. In both cases, the contrast existing between the “Castreja culture” circular houses and the italic model houses that succeeded them was recognised. In the residential area on the western slope, a set of six houses was documented, separated by several streets of irregular layout that were part of one of the neighbourhoods formalising the Roman residential unit. This unit is believed to have not been built before the middle of the 1^st century AD. Several different construction stages were registered and they originated the gradual replacement of the previous indigenous round houses.

The latest studies carried out in Tongobriga suggested that the city had entertainment buildings, with a theatre and an amphitheatre being a possibility. On the other hand, studies on the city’s urban fabric have been carried out following on the orientation of the civic group represented by the baths/forum (Rocha et al. 2014Rocha, C., Dias, L. and Alarcão, P. 2014: Tongobriga. Reflexões sobre o seu desenho urbano. CITCEM/Edições Afrontamento, Porto.).

3. THE ROMAN HOUSES OF TONGOBRIGA

The rationalisation process related with the construction layout and the reproduction of an architectural language of italic origin on behalf of the indigenous elites living in the Iberian Peninsula, in the context of the conquest of Hispania, confirmed the ability of Rome in attracting the local communities and integrating them into the new economic and social models dominating during the Roman control. In Tongobriga, these new models had an architectural expression in the remains that signalled what was old and associated with the indigenous identity, or what was new and Roman. It is also important to stress the physical proximity of the remains underlying the two cultural substrates. In terms of the dwellings, there was a reuse of materials resulting from the dismantling of the “Castreja culture” houses to build italic type residences, both in Flavian times and throughout the 2^nd century.

The areas known to have examples of Roman-style houses were located in the highest part of town, where there was a continuous evolutionary process when it came to the circular dwellings, which were destroyed and replaced with buildings with straight lines, and where the presence of the italic architectural lexicon can be appreciated. Amongst the new constructions, circulation spaces were designed with orientations that were out of the orthogonal grid of streets proposed for the foundational phase of the city. This assumes that there was a prior planning, although it was necessarily adapted to the territory, which had a well-marked slope (Rocha et al. 2014: 72-77Rocha, C., Dias, L. and Alarcão, P. 2014: Tongobriga. Reflexões sobre o seu desenho urbano. CITCEM/Edições Afrontamento, Porto.). In reality, the organisation of the streets and houses in the western residential area corroborated the irregularity of the blocks discovered, which may have resulted from the configuration of the previous family households, a well-known model in organising the residential areas of pre-Roman settlements in the region of the bracaraugustan Gallaecia, and which were usually bounded by walls.

When analysing the housing area on the western side, it was possible to identify a series of streets sensibly oriented towards NW/SE and NW/SW. Another element that allowed us to mark the layout and the orientation of the road axes was the entrance to the houses and the identification of some pipelines that carried out the drainage of dirty water under the roads. The analysis of these data suggested the existence of an attraction axis in the western direction, and it was possible to document this orientation in four houses (Fig. 3). The so-called ‘Well House’, located in the most eastern part of the housing unit, had three entrances, with the main one allowing the access to the atrium located in the western façade. It faced a NW/SE street and delimited the housing group including ‘Houses 1, 2 and 3’ and the ‘Impluvium House’. The presence of the other two entrances in the ‘Well House’ allowed us to assume the existence of two other streets, which flanked the house in the north and south. However, when analysing the other rooms’ tangent to the NW/SE street, we failed to identify any existing entrances in that same direction, with the exception of a taberna identified in ‘House 1’. The access to the ‘Impluvium House’, ‘Houses 2 and 3’ and the ‘Stairs House’ was made from an ENE-WSW oriented street. However, and although ‘House 1’ had an entrance from an inner corridor that divided the three houses from the block where they were built, this was a secondary entry point. The main entrance faces a street located on the north, which led to an open area. This was likely the most appropriate solution the owner found to maintain an ianua that would highlight his status through the use of italic lexicon in what concerns the compartments’ layout in relation to the entrances. This way, we concluded that there was a wide variety of solutions when it came to structuring the Tongobriga’s houses, and in their adaptation to the circulation spaces that seemed to divide the lots (Fig. 4).

3.1. The ‘Well House’/ ‘Casa do Poço’

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The ‘Well House’, built in the most eastern area of the western housing unit, had a rectangular plan and an area of about 300 m². This house was structured around a centred colonnade atrium, with a very elongated rectangular shape, and a size of 2.3 × 8.6 m. The open space was designed to follow the dimensions of the lot where the house was built. The interior of the house was accessed from a fauces connecting the south-western entrance to the central space (Leão 2012: 143Leão, A. 2012: Cidade romana de Tongóbriga. Contributos para a sua conservação e inteligibilidade, Ms. dissertation. Faculdade de Arquitetura da Universidade do Porto, Porto.). We emphasise that the said corridor was not centred around the colonnade, which may be associated with the proximity to the ENE-WSW oriented street.

This house saw the application of some concepts put forward by VitruviusVitruvius. 1934: On Architecture VI-X. Frank Granger (trans.). Loeb Classical Library 280, Harvard University Press, United Kingdom. for the construction of a house that intended to praise the social status of its owner. Thus, the compartments were perfectly symmetrical, and the main axis of the house was located in the alignment of the fauces, crossing the atrium and ending in a large space with a well that gave the house its name and also functioned as a support room. The identification of this hydraulic structure suggested the interpretation of the compartment as a culina, which would use the water to carry out activities related to food preparation and cleaning (Leão 2012: 143Leão, A. 2012: Cidade romana de Tongóbriga. Contributos para a sua conservação e inteligibilidade, Ms. dissertation. Faculdade de Arquitetura da Universidade do Porto, Porto.). However, the dimensions of this room, with about 27 m² and the supporting room, with about 11 m², exceed those expected for this type of space. Under these circumstances, it seems plausible to think that it could have been a reception room, or a representation one, which referred to areas more in line with the size and the prominent position of the compartment, which was probably a tablinum. Moreover, the space located around the atrium, in the northern part of the house, and with an approximate size to the previous compartment, was likely a representation chamber, traditionally interpreted as a triclinium. On the northern corner of the house, right next to the previous triclinium, we can find a compartment that probably performed representation functions, while its symmetrical opposite, south of the triclinium room, could have been a taberna, given its outside entrance. Similarly, it could also have been a bakery (Leão 2012: 143Leão, A. 2012: Cidade romana de Tongóbriga. Contributos para a sua conservação e inteligibilidade, Ms. dissertation. Faculdade de Arquitetura da Universidade do Porto, Porto.).

The remaining compartments seemed to have been dormitories or services. There was an identifiable functional division of the house between the public spaces, intended to welcome visitors and conduct business, and the areas associated with the private and domestic life of residents. The separation between these two types of spaces was rather unusual for a typical Roman house. The three compartments housing public functions were close to each other and located in the northern part of the house. Two of them had an entrance facing the atrium, and there was one centred around the portico’s columns in the open space (Fig. 5).

Figure 5.  a. Plan of the ‘Well House’/ ‘Casa do Poço’. b. 3D model of the ‘Well House’ (3D modelling software - SketchUp2018). 1. Detail of the wooden beams to support the roofs of the 1st floor and of the ambulacrum 2. plan of the house at 1st floor level. Author's drawing. c. Detail of the ruins of the ‘Well House’ ©Google Earth.

Considering the small size of the lot where this dwelling was located, it would have been impossible to expand on the rooms. The solution found was to build a first floor, which allowed the domestic space to grow. This hypothesis was based on how the walls were structured and over the assumption that there was a flat roof across the ambulacrum, with a possibility towards the recreation of the circulation space that was open on the ground floor, on the upper floor, and therefore duplicated the rooms, where the distribution layout remained.

3.2. The ‘Impluvium House’

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The ‘Impluvium House’ can be found in the southwest area of the ‘Well House’. It had a rectangular plan with an area of about 320 m². However, it had a slightly different internal logic, namely in terms of the use of the italic architectural lexicon. In reality, we are looking at an example of an atrium house with a well-preserved impluvium consisting of a floor made with granite slabs. The open space had about 8 m² and was characterised by the presence of six cylindrical columns that were arranged around the tank supporting the compluvium.

The longitudinal axis of the house followed an E/W direction. The entrance point articulated with a corridor connecting to the street and delimiting the house to the north, while giving access to a small vestibulum and from it to a fauces. At the end of the corridor, the atrium’s ambulacrum opened, and from which it was possible to access all the compartments of the house. The main axis led to a large room with an entrance perfectly centred with the two columns that closed the eastern part of the open space. Although this compartment is usually understood to be a culina (Leão 2012: 143Leão, A. 2012: Cidade romana de Tongóbriga. Contributos para a sua conservação e inteligibilidade, Ms. dissertation. Faculdade de Arquitetura da Universidade do Porto, Porto.), we believed it was too big to had been a kitchen (7.5 × 4.5 m). It had an area of about 35 m², and also exhibited a prominent position within the whole ensemble. These features are therefore more consistent with a representation room, possibly a triclinium.

To the south of the ambulacrum, there were two other rooms with significant sizes. One of them had an entrance perfectly aligned with the wall where it was located, and with an intercolumniation to the west of the atrium. The other room had a door aligned with the eastern part of the atrium corridor. Both compartments are believed to had been reception/representation rooms, which made all these types of rooms concentrated between the entrance area and the other side of the corridor. They were displayed around the open space and the southern part of the inner house. Regarding the interpretations put forward to these rooms, the first was classified as a triclinium and the other one as an exedra (Leão 2012: 142-143Leão, A. 2012: Cidade romana de Tongóbriga. Contributos para a sua conservação e inteligibilidade, Ms. dissertation. Faculdade de Arquitetura da Universidade do Porto, Porto.). However, given the centrality of the entrance of the first space in relation to the wall on which the door is located, as well as its width (about 1.5 m), we believe this compartment could have been a tablinum.

To the north of the atrium were the remaining housing spaces associated with the private domestic life, such as the cubicula, culina and cellae. In turn, the space located on the southwest corner of the house would certainly had been a taberna operated by the owner, given its openings to both the outside and inside (Leão 2012: 143Leão, A. 2012: Cidade romana de Tongóbriga. Contributos para a sua conservação e inteligibilidade, Ms. dissertation. Faculdade de Arquitetura da Universidade do Porto, Porto.). To the north of the fauces, there appeared to had been a stairwell that provided access to the first floor

Since the space available for the construction of the house likely restricted the ability to install the number of rooms the owner would have wanted, the solution found was to build a first floor that reproduced, both formally and volumetrically, the spaces on the ground floor. The distribution and circulation through the rooms on the upper floor was facilitated by the construction of two staircases, one flanking the fauces and the other one located in the middle of the impluvium (Fig. 6).

Figure 6.  a. Plan of the ‘Impluvium House’ and ‘Stairs House’. b. 3D model of the ‘Impluvium House’ where it can be seen that the floor (2) reproduced, formally and volumetrically, the spaces of the ground floor (1). Author’s drawing in SketchUp2018. c. Detail of the ruins of the ‘Impluvium House’ ©Google Earth.

The ‘Impluvium House’ is a prime example in understanding how the peristyle was accepted in residences used by the north-western populations of the Iberian Peninsula in the 1^st and 2^nd centuries. The truth is that this element of italic houses combined the distribution functions of a patio with the representative value of the atrium/vestibule. The house documents the adaptation of the Italian architectural lexicon to the needs and tastes of the owners, both in terms of the functionality of compartments and the shape of their plans, which followed some of Vitruvian’s guidelines when it came to the layout and the size of spaces designed to enhance the social status of the paterfamilias.

3.3. The ‘Stairs House’ / ‘Casa das Escadas’

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This house had a lateral atrium located on the southwest corner of the lot, and this position may be connected with its reduced size, with about 200 m², a feature that conditioned the loss of the ordering character of an open space and its ability to house larger compartments. In this way, the access to the house was made from the street that also served the ‘Impluvium House’. Next to the door, three steps have been identified and these certainly helped with the unevenness of the unit’s interior in relation to the road axis. This element was not present in the house located to the east, precisely due to the existence of a corridor that allowed the gradual overcome of the different circulation levels. After the stairs, there was a fauces that connected both the atrium and the rooms in the house. In reality, the distributing element of the internal spaces in this dwelling was this corridor and not an open space. It is from it that all areas of the house were accessed.

In this house, there were five compartments that have been difficult to interpret, due to the lack of materials indicating the activities occurring inside. Adding to this, there were no architectural elements that allowed the analyses of their functions. However, it seemed plausible to propose that the open space located on the eastern part of the fauces, with a support room, could have been a triclinium, while the remaining spaces could have fulfilled the functions of cubicula or performed the role of culina and cellae, an interpretation that should be accepted with due reservations (Leão 2012: 145Leão, A. 2012: Cidade romana de Tongóbriga. Contributos para a sua conservação e inteligibilidade, Ms. dissertation. Faculdade de Arquitetura da Universidade do Porto, Porto.). In reality, there were three large compartments, one with a supporting room and a narrower space with about 0.80 m wide, and which may have functioned as a stairway leading to a first floor, reserved for the private rooms. If this was the case, the rooms on the ground floor had an exclusively public use, namely a tablinum, located on the western part of the fauces and an exedra, located to the east of the atrium.

Despite there being some doubts with regards to the interpretation of this dwelling, it seemed possible to think that its owner tried to adapt some italic elements that were typical of a Roman elite house to a relatively modest space, which meant the loss of the areas that were missing. An example of this is the maintenance of a longitudinal axis that, starting from the ianua, crossed the fauces and led to the atrium. If in a typical italic house, the open space was the element associated with the capture of rainwater and the organisation and distribution of the housing compartments, in this case it did not perform any of these functions, and no impluvium has been identified. The only passage associated with the atrium is the one giving access to it, so there seemed to had been a secondary addition of the italic elements to the house. This reiterated the roman status of the owner; however, had no architectural expression in the way the house structural axes were organised.

Due to the small size of the lot where the house was located, the owner likely decided to build a first floor that allowed the formal and volumetric duplication of the ground floor rooms. The solution found for the distribution of spaces on the upper floor, given that the open area was located on the longitudinal limit instead of being centred, was to use the space that corresponded to the fauces as the distributor element of the upper rooms (Fig. 7).

Figure 7.  a. Plan of the ‘Stairs House’ and ‘Impluvium House’. b. 3D model of the ‘Stairs House’ (3D modelling software - SketchUp2018). 1) Geometrization of the conserved remains; 2) Identification of the inner courtyard; 3) Hypothesis for the distribution of the upper floor; 4) Complete reconstruction of the house. Author’s drawing. c. Detail of the ruins of the ‘Stairs House’ ©Google Earth.

Despite the constraints caused by the small size of the plot, the owner seemed to have not spared any effort in adding a degree of monumentality to this dwelling, which was visible at the entrance point. Two columns can be seen flanking the ianua and the stairs providing access to interior of the building. These elements suggested that the social areas used for banquets could have been located on the upper floor. This is not the traditional typological evolution, but rather an adaptation of the architectural project to the size of the plot, to the economic availability of the owner and to their demands when it came to exploit the house full potential.

3.4. The ‘Houses 1, 2, 3 and 4’

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The set of ruins identified in the north-western part of the western housing area presented some interpretation challenges due to the complexity of the remains found and their fragmentary character (Dias 2003: 85Dias, L. 2003: Área Arqueológica do Freixo. Futuro? Tongobriga. Breves Reflexões. IPPAR, Lisbon.; Rocha et al. 2014: 73-74Rocha, C., Dias, L. and Alarcão, P. 2014: Tongobriga. Reflexões sobre o seu desenho urbano. CITCEM/Edições Afrontamento, Porto.; Leão 2012: 142-145Leão, A. 2012: Cidade romana de Tongóbriga. Contributos para a sua conservação e inteligibilidade, Ms. dissertation. Faculdade de Arquitetura da Universidade do Porto, Porto.). However, we believe it was possible to restore the layout of the four dwellings, two of which occupied the southern part of the block, with ‘House 2’ to the west and ‘House 3’ to the east, while the northern part of the block was occupied by ‘House 1’ and ‘House 4’. These were domestic units that sought to take advantage of the shapes and sizes of the lots. They were therefore irregular and uneven. The housing complex was structured around a corridor that was located at the centre of the block, which was used as a secondary access area to the houses. The main entrances were articulated with streets running to the south and the north. In turn, the identification in two rooms of this broad insula of a forge and an oven on the northwest corner, allowed the suggestion over the existence of commercial activities taking place in this block, although little is known about the nature of these practices (Fig. 8).

Figure 8.  a. Plan of the central insula of Tongobriga housing area. b. The 3D model of ‘House 4’ represents the interpretative process for architectural reconstruction. 1 and 2) geometrization of the preserved remains; 3) restitution of the ground floor; 4) proposed solution for wooden beams; 5) restitution of the second floor; 6) restitution of the roofs of the building with possible formalization of the façade. Author’s drawing in SketchUp2018. c. Detail of the ruins of the central insula of housing area ©Google Earth.

‘House 1’, located on the northern border of the insula, had a side atrium at the end of a fauces that was organised from the entrance point and arranged in the N/S direction. The open area did not perform the function of ordering the surrounding space, being this function performed by two corridors, one on the longitudinal axis and represented by the fauces, and the other on the transverse axis and cutting through the previous one, just before the atrium antechamber. The compartments were difficult to interpret, as we only had the walls’ axes. It seemed safe to assume that the room located on the northeast corner could have had reception/representation functions due to its size, the same with the compartment located to the western side of the secondary entrance, which appeared to be a triclinium with a supporting room. Given the lack of data, the remaining spaces in the house provided no further clues, but they may have had similar uses, while the area reserved for domestic activities could have been carried out on the first floor, which was accessed from a set of stairs located in the atrium area.

On the other hand, it was possible to identify four tabernae, two of which represented by the compartments with the remains of an oven, located in the west part of the house and another, with a furnace, to the west of the fauces. It was likely explored by the owner, if we consider a door that connected to the entrance hall. Added to these two was another shop located in the eastern part of the building, with a possible first floor, as well as another one located on the northwest corner, where a counter was also identified.

‘House 2’ corresponded to a residence with a central atrium and a south entrance without fauces, vestibulum or any other space delimiting the ambulacrum’s ianua in the open space. Although uncommon, this solution allowed the widening of the internal area, which would necessarily be affected if the symmetry of the spaces was to be maintained. Considering the scarcity of data, it seemed that the plan for this house shared some similarities with the proposal put forward for the potential first floor of the ‘Stairs House’. In fact, the three compartments located on the ground floor, arranged around the open space, were too large to have been used as reception/representation rooms. Under these circumstances, the domestic spaces would have been on the upper floor, and were structured around the atrium’s compluvium.

‘House 3’ had a completely different typology from the others, and there has been a lack of data to suggest an open space or any other ordering element. The layout of this dwelling seemed to be closer to the ‘linear taberna type’ of residences identified in Ampurias, as it had two adjoining spaces. One of them opening directly to the street, where commercial activities were to be carried out, and another located in the rear back, which would have functioned as a cella or even as a residence (Mar and Ruiz 1993: 349-353Mar, R. and Ruiz de Arbulo, J. 1993: Ampurias romana. História, arquitectura y arqueologia. Ed. Ausa, Sabadell.). However, the two compartments could have exclusively functioned as a tabernae, and the commercial activity could have been carried out in the southern part. The other space was likely reserved for the storage of products or for their manufacture. This suggestion is based on the extension of the block towards the east, and beyond the limits of these structures, which suggested the existence of side stairs that would give access to a first floor, where the private rooms would have been located.

Finally, we identified ‘House 4’ with a typology of ‘linear tabernae type’, very similar to ‘House 3’, as well as to those identified in Ampurias (Mar and Ruiz 1993: 349-353Mar, R. and Ruiz de Arbulo, J. 1993: Ampurias romana. História, arquitectura y arqueologia. Ed. Ausa, Sabadell.). It was a small house on the ground floor with an upper floor that was identified from the state of conservation of the perimeter walls. Inside, the base of a wooden staircase was preserved. Since the space available for the construction of the house was reduced, the ground floor was likely used as a production and commercial space, with the residential areas occupying the upper floor, where it was possible to build two spaces with sufficient dimensions for the typical household chores.

4. DISCUSSION AND INTERPRETATION

The group of Roman houses built between the 1^st and 2^nd centuries in Tongobriga and which we have just analysed, is a notable example of the way in which the idea of a dense and winding Mediterranean urban space developed amongst the populations of the Iberian northwest, not only due to the irregular layout of the streets, but also for the presence of, at least, one dead-end street that provided access to the inner spaces in one of the blocks. The existence of access stairs to the upper floors seemed to confirm the intensive nature of the construction process, also documented in other cities of Hispania in much earlier chronological contexts. This was the case with the Hellenistic neighbourhood of Neapolis in Ampurias (Mar and Ruiz 1993Mar, R. and Ruiz de Arbulo, J. 1993: Ampurias romana. História, arquitectura y arqueologia. Ed. Ausa, Sabadell.). Some indigenous settlements in northern Africa, as for example Dougga and Tiddis, amongst others, witnessed a similar evolutionary pattern, which saw the old streets of the pre-Roman settlement, of irregular layout and adapted to the topography of the slopes, being densified with the construction of two floor houses (Khanoussi 2002Khanoussi, M. 2002: Dougga. Ministère de la culture (Tunisie), Institut national du patrimoine,Tunísia.). In Italy as well, in the 2^nd century, the densification example of the port city of Ostia is remarkable, albeit on a very broader scale, as the houses on site ended up having five floors (Mar 2002Mar, R. 2002. “Ostia, una ciudad modelada por el comercio. La construcción del foro”, Mélanges de l’Ecole Française de Rome, 114 (1), pp. 111-180. Paris/Rome.). The case of Ostia revealed how the densification of urban centres was a consequence of the development of urban activities, not only of a residential nature, but also commercial and productive.

The residential set of Tongobriga clearly showed the same type of evolution in terms of how the urban space was thought, and how it was densified by the increased number of population and activities. Consequentially, the proliferation of the plumbing network around the analysed housing area, allowed us to perceive that more than residential needs, there was a presence of several production activities, which, alongside the commercial businesses linked to the tabernae occupying some of the façades, would have entailed an intense everyday life that certainly animated the residential areas of Tongobriga (Leão 2012Leão, A. 2012: Cidade romana de Tongóbriga. Contributos para a sua conservação e inteligibilidade, Ms. dissertation. Faculdade de Arquitetura da Universidade do Porto, Porto.; Rocha et al. 2014Rocha, C., Dias, L. and Alarcão, P. 2014: Tongobriga. Reflexões sobre o seu desenho urbano. CITCEM/Edições Afrontamento, Porto.).

On the other hand, the analysis of known Roman houses provided us with very significant data regarding the understanding of how domestic units adopted different architectural solutions, in order to apply the italic grammar, without being submersed into a rigid urban grid that delimited blocks and divided them into lots. In reality, the variable sizes and orientations of the lots seemed to constitute the main conditioning elements of the plants, and the distribution of the houses’ inner spaces, to which would have been added the status and the economic strength of the owners. What seemed to stand out from the analysis of the preserved remains in these new typology dwellings was the repetition of architectural elements of italic matrix, although these seemed to have been almost forcibly applied. Given the physical features of the lots, it was therefore necessary to adapt several spaces, even if this resulted in the loss of their initial functions, as it happened with the atria in the ‘Stairs House’ and ‘House 1’ that failed to assume a real ordering role of the compartments, or the lack of a space separating the ianua from the ambulacrum in the ‘House 2’ atrium.

Thus, the solution found by the owners to give form and create the necessary compartments, whilst ensuring that there was enough space to carry out the activities required by the family life and those of representation, the latter being necessarily adjusted to the social level and the wealth of the owners, was to grow the house vertically. This was a phenomenon identified in all the analysed dwellings in Tongobriga. The idea of building a first floor to group all the spaces needed for the overall functioning of a house, and mainly associated with the domestic and private life, as the cubicula, enabled the ground floor to be used as a reception area and a place to house representation activities. It was therefore possible to build large triclinia and tablina.

The sizes of the lots were an important variable to consider when assessing the features of the house plans, since they influenced the organisation of the inner spaces. Sometimes it was necessary to retreat an open area, or to even sacrifice part of its ambulacrum, by narrowing it down, while trying to maintain its ordering function. There were cases however in which this function disappeared completely, and the open area functioned not as a distributor element, but rather as a point of light and ventilation. This was likely the case with ‘House 1’ and the ‘Stairs House’. Having said this, it is important to recognise that the Roman household should not be understood as a model to be faithfully reproduced; it is not a rigid typology, but should rather be viewed as a language and a lexicon represented by different architectural solutions that have been combined in very flexible ways and according to the requirements and the economic power of the lot owners.

5. FINAL CONSIDERATIONS

The Roman house seen as a cultural artefact, can never be presumed to follow a closed typology, but rather a multiplicity of architectural solutions. The background was the defining element of the house and shaped its architectural project, which was, in turn, determined by the city’s specificities, as for example the topography, the urban fabric, but also the status and the financial strength of those who commissioned the works (Beltrán and Mostalac 1994Beltrán Lloris, M. and Mostalac Carrillo, A. 1994: Colonia Victrix lulia Lepida-Celsa II: Estratigrafía y pinturas. Institución Fernando el Católico, Zaragoza.).

We are therefore far away from the Vitruvian guidelines for the elite Roman house, which would preferably follow a rectangular plan and require a large area intended to accommodate atria et peristylia amplissima and laxiores ambulationes (Vitr., De arch., VI.V.2). The truth is that this is not what happened in most Hispanic cities, regardless of them having or not a Roman foundation. If we consider that the clusters of imperial foundation had orthogonal urban layouts, and generally had blocks with well-defined limits and plots of standardised sizes that were never too large, we have to admit that it would have been very difficult to accommodate the construction of wide domus, as the ones documented in cities with no orthogonal layout. A few examples of the latter are Conimbriga’s ‘Cantaber House’ and the ‘Repuxos House’, and Ampurias’ ‘Peristyle House’, or even the last stage of ‘House 2’.

There seemed to be no specific identity or model for a Roman house that has been unchangeable in time and space, as the houses have undergone several reconstructions and transformations over time. As we noted in the houses of Tongobriga, there was a great diversity in construction solutions, with details that must be assessed in both spatial and temporal terms, due to the heterogeneity of cities and their elites. This seems to shed some light in understanding certain regional traits, the change in paradigms, ideologies, ways of life, and even in the simple tastes of owners and architects. All these have the ability to influence the characteristics of the changes that have taken place in residences over time (Magalhães 2019Magalhães, M. 2019: A domus Romana no Noroeste Peninsular: Construção, Arquitetura e Sociabilidades, Ph.D. thesis. Universidade do Minho, Braga.).

The analysis of the examples of Tongobriga allows us to conclude that the Roman house cannot be understood as the result neither of the repetition of a repetitive and unique model of a scheme of organization of the house based on an axial system of organization of the compartments, present in the Pompeian house, nor of the application of a rigid typology that defined the characteristics of a house of atrium, of a house of peristyle or a house of atrium and peristyle. It would be more correct to understand the roman house as a language, necessarily variable in morphological terms, but also as a lexicon, composed of grammatical units that express several semantic possibilities, harmoniously solved in the architectonic solution that configures the syntax of the dwelling, which is necessarily result of several factors, but above all a clear reflection of the activities of the owner and of his family and of the necessities arising from the public exhibition of his status in the civic structure of the cities. In truth, the roman house was the mirror of the class and wealth of its occupants, reflecting in its architectonic characteristics the social status of its occupants, so the house worked with a powerful language that in a little literate society transmitted logics of power, privileges and values. In this way, the domus were the main scenario of the political and social life of their owners, establishing the physical display of their economic power, operating as a structure of representation and social control.