1. Introduction
The spatial development of the City of Dubrovnik has been shaped by its rich history, proximity to the sea, and connectedness with the surrounding areas. This development represents an interesting story about balancing urban expansion and preserving the coastline and the islands, as well as thoughtful hinterland development. In Dubrovnik, the area of Gruž Bay is organized as the main city harbor and a trading center. However, it is also a city district where a large number of historic summer residences are located.
The architecture of summer residences in the Dubrovnik region represents elements of cultural and historical heritage that both enhance the landscape and bear witness to the rich legacy rooted in the native Mediterranean ambience. These magnificent complexes, characteristic of the Dubrovnik coastal region, not only served as destinations for a summer getaway from the city’s bustle but also reflected the social status and aesthetic preferences of their owners (
Figure 1).
By familiarizing ourselves with the specific spatial characteristics that define Dubrovnik’s summer residences, this research aimed to comprehend their urban and architectural essence and determine the possibilities of using the typology of these residences as a tool for planning the balanced development of both the private and societal aspects of the city, in accordance with the paradigms of the New European Bauhaus [
1,
2].
Historic Dubrovnik summer residences (DSRs) stand out for their harmonious integration with their natural surroundings, employing local materials such as stone and wood to achieve an authentic aesthetic [
3]. Spacious terraces, arcades, and water features allowed for excellent air circulation and ensured a comfortable stay during the warm summer months. As a result, these summer residences have become known for their ability to provide intimacy and comfort within their walls, which were also open to their surrounding environments [
4,
5,
6,
7] (
Figure 2).
In 1440, Filip de Diversis described Gruž as a place “(...) where the view opens to the most sheltered and magnificent harbor, curved like an arch and adorned all around with numerous fertile vineyards, majestic palaces, and beautiful gardens”. In the same section, it was stated that there are attractive vineyards and private residences with gardens on both sides of the part of the city known as Rijeka Dubrovačka. The choice of words is deliberate: in Gruž, the text refers to “grand palaces and delightful gardens”, whereas in Rijeka Dubrovačka, it only mentions “private houses with gardens”. Archival sources indicate that summer residences in Gruž Bay were already present in the 14th century, and by the mid-15th century, the bay had become an exclusive area for Dubrovnik’s summer retreats [
5].
The Gruž coastline has undergone numerous urban transformations, from historical industrial developments to contemporary tourism-related changes [
9]. This has included the development of a nautical marina and a cruise port, along with an increase in accompanying service and accommodation capacities, as well as planned spatial development [
10]. One of the problems that arise during the construction of new buildings on the coast stems from the phenomenon of mass tourism and its negative impact on the local population. This has been corroborated by studies that have explored the coastal areas with a focus on tourism issues, traffic, and the disruption of the coastline’s urban fabric [
11]. Therefore, one can raise the question of whether new urban complexes can take on the task of mitigating the negative impacts of tourism and building upon the spatial characteristics of Dubrovnik’s summer residences while promoting the coexistence of privacy and sociality [
12]. This topic becomes important as efforts are made to preserve the authentic urban environments and specific spatial features when undertaking new construction projects along the coastal areas of the city. We are witnessing more and more changes in the existing environments where new buildings are emerging and occupying previously undeveloped urban areas, creating heterogeneous spaces with different environmental, architectural, and urban expressions [
10].
The importance of researching this issue is further confirmed in the Management Plan for the Protected Heritage Complex of the City of Dubrovnik, which was developed with the aim of striking a balance between the protection and restoration of the architectural heritage and the economic development, functionality, and vitality of the city, and not just for the preservation of the historical core and historical buildings. In doing so, it is emphasized that approaches to protect various aspects (heritage-based, environmental, economic, and sociocultural) should be mutually complementary to preserve the authenticity of Dubrovnik’s historical layers [
13]. The most significant challenges in management can be found in thematic areas: planning, protection and preservation, sustainable development, tourism, transportation, and risks [
14]. There is a distinct need for collaborative urban and environmental development planning with an equal measure of problem assessment. It has been suggested that protection and preservation should find a balance between urban expansion and the preservation of the historical urban landscape, which is an important component of UNESCO cultural heritage. Proposed development solutions should achieve harmony between the new and the old, emphasizing all aspects of Dubrovnik’s outstanding universal value. Emphasis has been placed on the fact that the sustainable development of Dubrovnik is imperative for preserving its authenticity and the quality of life of the local population. The suggestion is to focus on socially, economically, environmentally, and culturally enriching tourism that would play a significant role in local communities. It has been observed that sustainable traffic organization in Dubrovnik is a crucial need because the city is facing challenges of above-average traffic congestion, especially during summer crowding. The risks are recognized, as well as the need to ensure a healthy and safe environment to address climate change, which includes reducing pollution, protecting natural resources such as the sea and air, and preserving the city’s parks and green areas.
Considering all this, it is necessary to identify the highest-quality and most unique forms of construction while determining the possibilities of their contemporary urban counterparts, as has been indicated in research concerning the impact of sociocultural factors on changes in traditional residential architecture [
15]. Previous experiences have indicated the possibility of losing authenticity and cohesion in the urban fabric due to the lack of specifically designed guidelines for using space and construction. They have also highlighted the need for the establishment of improved planning tools that will encourage the development of more layered forms of sociality integrated into urban environments [
13].
The aim of this paper is to determine the characteristics of historic DSRs expressed through contemporary spatial parameters for urban development planning. By understanding the past and adapting to the present, the goal is to shape complexes that will not only inherit the aesthetics and function of the original summer residences but also contribute to the preservation of their identity in creating recognizable forms of coexistence between privacy and sociality along the Dubrovnik coastline [
16].
2. Materials and Methods
This study identified the distinctive indicators of the spatial parameters of the existing historic DSRs in Gruž (
Figure 3) and then analyzed them according to types of spatial planning conditions to guide the construction and development of building plots [
16]. A total of 18 historic summer residences were analyzed: Ghetaldi–Gondola–Solitudo, Pucić–Kosor, Petar Sorkočević, Gundulić–Zago, Bonda–Majstorović, Gradi–Vuić, Junije Bunić, Marin Bunić, Paladin Gundulić, Kaboga–Zec, Bobaljević–Pucić, Natali Sorkočević, Miho Bunić, and Stay. The analysis excluded the summer residences whose plots and gardens had been confiscated over time (Giorgi–Matijević and Bassegli Gozze) and those that had been converted into hotel and hospitality buildings (Zamagna–Kazbek and Pucić–Pitarević). The research was conducted using a model representation of the spatial indicators of the summer residences (
Figure 4) based on data from cadastral maps and land registries [
17], topographic maps, satellite imagery, and urban plans [
10,
18,
19,
20], a 3D city model [
21], and the literature, as well as textual data sources [
3,
4,
5,
6,
7,
8,
9,
13].
The model provides plans for the spatial organization of DSR complexes on the Gruž coast in order to define their spatial composition, their floor layout disposition, the relationships between the built, residential, and auxiliary parts of the complexes, and the landscaped areas of the plots.
The spatial composition of the plots, having a prominent relationship with the sea and the coastline, was based on graphical data from satellite maps, which were cross-referenced and supplemented with information from topographic maps and urban plans. The floor layout of the buildings on the plot was based on data from cadastral maps and representations from the 3D city model. The surface areas of the plots and the built portions of the complexes were extracted as numerical data from land registries. The surface areas of the landscaped parts of the plots were obtained by calculating the difference between the total plot surface area and the surface area of the built portions of a complex, with additional information derived from satellite maps. Literature and textual data sources were used to complement and verify the graphical elements of the model’s representation, as well as to establish numerical data regarding the characteristics of the summer residences. Additionally, a field survey was conducted across the entire area of the researched summer residences to confirm all the data from the model’s representation.
The collected model data were systematically organized, highlighting the characteristics of the urban and architectural spatial indicators in a clear and structured manner. The spatial indicators were separated according to their themes to serve as provisions for the implementation of urban plans and spatial plans [
10,
18] (
Table 1).
This research investigated urban spatial indicators, including plot size, the proportion of built-up areas, the proportion of landscaped areas, integration with the natural terrain, fencing, road–pedestrian access, and sea moorings (
Table 2). Subsequently, architectural spatial indicators were also examined, including the ground floor’s floor area, total floor area, height, number of floors, floor plan shape, residential area, auxiliary area, division of the residential section into 1 large and 4 small rooms, and orsans (boathouses) (
Table 3).
The average values of the obtained data were determined, and the characteristics of the typology of the summer residences are presented. The average values of the indicators of the historic summer residences formed the basis for expressing the characteristics of the typology of these residences while data were aligned across all types of urban and architectural spatial indicators. Subsequently, an analysis was conducted on the identified spatial indicators for the summer residences and spatial indicators for residential planning in the urban development plans of the city (
Figure 5 and
Figure 6). The spatial indicators of residential planning were taken from the provisions for the implementation of urban plans for Dubrovnik.
The obtained results were compared with those of other research, after which, conclusions were drawn regarding the possibilities of using the typology of DSRs as a spatial planning tool for the development of the coexistence between privacy and sociality.
This research delved at a finer scale compared to previous studies, focusing specifically on the dimensions of individual plots and architectural buildings, such as DSRs and the plots belonging to them. However, it is important to note that this research was limited to this narrower scope. Despite this, there is potential to expand this study. Using the indices listed in
Spacematrix: Space, Density and Form by Meta Berghauser Pont and Per Haupt, a more expansive urban landscape could be systematically explored [
22]. These three key indicators are the surface area index (FSI), surface area index (GSI), and network density (N) which are used to draw productive conclusions about urban form and performance. This quantitative approach would enable a comprehensive analysis of the wider urban fabric, evaluating the influence of these parameters on the architectural evolution of the city, instead of exclusively concentrating on a single architectural entity.
In addition, the research could have taken a comprehensive approach to the revitalization of cultural heritage, evolving from an initial focus on individual buildings towards a broader view of the cultural landscape as a connected system of the anthropogenic and natural environments, which was implemented in
The Heritage Urbanism Method by Mladen Obad Šćitaroci, Bojana Bojanić Obad Šćitaroci, and Ana Mrđa [
23]. In this method, identity factors, influencing factors, and value factors are analyzed. Then, the criteria for new interventions, improvement, and revitalization can be defined. However, in this research, we wanted to keep the focus on the urban and architectural features of DSRs and determine which of their specificities can influence the development of the coexistence of privacy and sociality.
4. Conclusions
A model analysis of urban and architectural parameters was conducted on 18 historic summer residences in the coastal area of Gruž. It was based on a model representation with data from cadastral maps and land registers, topographic maps, satellite imagery, urban plans, 3D city models, the literature, and textual data sources, as well as data obtained through field surveys. The urban indicators studied included the plot area, percentage of built-up areas, percentage of landscaped garden areas, integration into the natural terrain, enclosure, vehicular and pedestrian access, and sea access. In addition to those, the following architectural indicators were investigated: the ground floor area, total floor area, height, number of stories, floor plan shape, residential area, auxiliary area, division of the residential area into one large and four small rooms, and boathouses. The limitations of the research results stem from the precision of the numerical and graphical model data.
The research identified specific spatial characteristics of summer residences that have the potential for contemporary use, which concerned the topics of plot, house, garden, technological innovations, and privacy and sociality.
Plot: With a surface area of 3500 m2, DSR plots differ significantly from the plots of residential houses and villas with cultivated green areas. Although the plots of summer residences have been used during the city’s development, they have not yet been planned for new developments in the spatial planning documents for future city development.
House: With a surface area of 1120 m2, DSRs have the same house surface area as villas with cultivated green areas, but they have two wings that form an L-shaped floor plan. The two-story residential part makes up 60% of the surface area, while the single-story auxiliary part constitutes 40% of the surface area. The house is organized in such a way that the flat roof of the single-story section is used as a raised terrace that extends deeply into the garden areas of the plot, establishing intimate contact with the natural surroundings.
Garden: With a surface area of 2800 m2, the garden is the essence of a DSR, revealing characteristics of adaptability and multifunctionality, making up almost 80% of the total surface area of the plot, unlike the gardens of residential houses, which constitute 30%, or those of villas with cultivated green areas, which make up 50% of the plot surface area.
Technological innovations: These play a significant role in shaping the design and functionality of DSR complexes. Unlike residential houses and villas with cultivated green areas, these complexes can, due to their spatial characteristics, serve as open arenas for experiments and the implementation of innovative advances and technological progress.
Privacy and sociality: DSRs have a total floor area three times smaller than the surface area of the garden. In contrast, residential houses have a total floor area that is four times larger than the garden surface area, while villas with cultivated green areas have a total floor area equal to the garden surface area. Based on historical experiences of using summer residences, the relationship between enclosed and open spaces, where open spaces are predominantly larger, opens up the possibility for developing different forms of coexistence between privacy and sociality.
The recognized specificities suggest that the typology of DSRs can be used as an exceptionally important urban planning tool for the development of the city’s urbanity because it is characterized by a presence in numerous locations along the coast, a large enclosed plot, a large house with two wings for different purposes, and a large garden for various forms of use, enabling the implementation of technological innovations and the development of the coexistence between privacy and socializing.
Examples of the renovation of DSRs show that it is possible to develop the coexistence of privacy and sociality, influence urban development, and encourage social interaction. The Petar Sorkočević summer residence is used by the Croatian Academy of Sciences and Arts for its activities. The summer residence by Miho Bunić is owned by the City of Dubrovnik and used by the Croatian Restoration Institute. Both summer residences have private regimes of use, but at the same time, they are open to visitors, and parts of their closed and open spaces are used for cultural events. The summer residence Sorkočević in Rijeka Dubrovačka, located in the neighboring bay, is owned by the company ACI Marina Komolac and has parts that are for private use. The summer residence is being renovated so that part of the closed interior space can be used as an interpretation center for the presentation of the culture of leisure, and the open exterior space for the presentation of the ambience of the Renaissance Garden. In this way, the summer residence also becomes a place of urban sociality. These examples indicate that the features of summer houses are protected and improved via their social use. Urban transformations, while preserving, restoring, and adapting historical residences, as well as constructing new complexes within the typological framework of DSRs, can create a space that respects private needs while simultaneously encouraging social interactions, the exchange of ideas, and the preservation of the cultural identity of the city and its inhabitants.
The characteristics of DSRs support the fundamental values of the New European Bauhaus—attractiveness, inclusiveness, and sustainability. In addition to realizing the convergence of the relationship “property–society–sustainability”, DSRs could also be a medium for implementing the thematic axes of the New European Bauhaus when planning urban development: reconnecting with nature, restoring the sense of belonging and connecting residents, prioritizing places and the people who need them most, and achieving circular sustainability and long-term development goals [
1,
2].
However, when determining the direction of the future development of the city, it is necessary to include other aspects that affect the space, such as tourism, or tasks from the management plan, to determine whether there is a possibility of implementing an organizational typology that affirms the advantages of a complex with greater open outdoor spaces than enclosed interior spaces. In addition, other approaches are possible, unique to each DSR, which could result from quantitative and qualitative considerations of the expressed indices that have specific lines of use. The research results can be used in the development of urban and spatial plans, both for conceptualizing their development solutions and shaping their provisions for implementation. Moreover, they contribute to our understanding of the position of the typology of DSRs in relation to contemporary typological forms.
Continuing research can be directed towards verifying the identified features of all parts of Dubrovnik and its urban region where the typology of DSRs appears. Furthermore, expanding this research is possible through a comparison of the characteristics of historical summer residences throughout the entire Mediterranean region while determining their contemporary functions and influence on the development of cities. Research can also be developed in the direction of determining the implementation model for the guidelines of the New European Bauhaus using the typology of DSRs. It is also possible to conduct a more expansive “Spacematrix” study of the urban landscape with the application of indexes of space, surface, and density, which are used to draw productive conclusions about the influence of the urban form of DSRs on the architectural evolution of the city. Likewise, in the continuation of the research of this thematic framework, with the use of the heritage urbanism method, the criteria could be determined for new operations and the improvement and revitalization of DSRs.
Dubrovnik summer residences are an extremely important part of cultural and architectural heritage, and their revival and social reuse are becoming key issues in the contemporary urban environment. This article has been dedicated to the study of the heritage system of DSRs, with a special emphasis on architectural typologies, with the aim of demonstrating their potential for social reuse. The goal was to examine how architectural typologies can serve as valuable spatial planning tools. The first key contribution of this study lies in understanding the value of architectural typology as a spatial planning tool. The analysis of different typologies enables a deeper understanding of the architectural diversity of DSRs and, thus, a better understanding of their spatial relationships and functions. This understanding provides a basis for the development of sustainable urban strategies that ensure the coexistence of cultural heritage and the contemporary needs of communities. The next step in this research is creating a general urban plan and defining a new type of plot. This approach makes it possible to identify the common characteristics of DSRs, which helps in the planning and implementation of revitalization. This study contributes to the revitalization of existing summer residences by providing guidelines for their renovation and rehabilitation according to modern standards. Through a careful analysis of the typology of the building, this study has identified potential methods to maintain the authenticity of DSRs while adapting their functionality to the contemporary needs of the community. Special emphasis was placed on their Mediterranean background and the way the summer residences fit into the environment. The research considered how larger DSR plots, as well as the planning design of plots of the same type, could help protect green areas and incorporate missing public facilities into the urban structure. This approach contributes to the sustainable development of the city, protects the authenticity of the space, and encourages the joint use of resources. The analysis of architectural typologies opens up new perspectives on spatial planning while encouraging the revitalization and preservation of cultural heritage according to the needs of modern society. The examples of renovated DSRs demonstrate the feasibility of integrating historic buildings into contemporary urban life, encouraging social interaction, and preserving cultural identity. This article paves the way for further research, encouraging the development of urban and spatial planning that resonates with the changing needs of contemporary society.