THE STUDY OF DEPOPULATED HISTORICAL ENSEMBLES IN THE PROVINCE OF TERUEL: A TOOL TO MAP, PROTECT AND CONSERVE THEIR VERNACULAR HERITAGE AND IDENTITY

There are 23 rural historical ensembles listed as BIC in the province of Teruel, one of the most depopulated areas in Spain. On the one hand, the lack of economic and demographic pressure in this region has made it possible to preserve many of the typological features of their vernacular architecture. On the other hand, the loss of permanent inhabitants and skilled craftsmanship practitioners has led to a worrying lack of maintenance and abandonment, which threatens their future conservation. The Cultural Heritage Department (Gobierno de Aragón) has been promoting several studies aimed at the protection of 6 different listed case-studies (Albalate del Arzobispo, Calaceite, Rubielos de Mora, Mirambel, Beceite and Teruel). Despite being very small, municipalities are the only competent bodies for the elaboration of the Special Protection master plans of each HE, according to Urban Planning and Cultural Heritage legislation. Hence, the primary purpose of these studies is to support them by analysing their heritage significance and singularities so they can use them as the base for master plans. They will also help raise awareness of their cultural values among local communities, while avoiding the mere conservation of empty urban and rural landscapes. The methodology comprises the identification, analysis and diagnosis of the heritage values that build their identity, thanks to a thorough inventory of all the vernacular constructive techniques, components and zones with a distinguishable character within the urban tissue and its environment.


Context
The province of Teruel is one of the three provinces in Aragón, a region located in the North-East of Spain.
Like other countries, Spain has an irregular demographic distribution, since most of its population is concentrated both on the coastline and the capital, Madrid. Because of that, most inland areas suffer from particularly low population density, and the zone of Teruel is no exception. Despite its size, 18,810 km2, the exodus to urban centres, together with the negative natural growth, has led to an inevitable demographic desertification. In fact, only 134,137 inhabitants (INE, 2019), which makes an average population density of only 7.13 inhabitants/km 2 .
According to a report by the Centre for Studies on Depopulation and Development of Rural Areas, CEDDAR (Pinilla et al., 2017), this situation is a symptom of serious structural problems that make policy-making very crucial at this stage. The worrying lack of economic and social dynamism in rural areas has made it possible to preserve its vernacular architecture from major modifications or even demolishment.

Legislative framework
The highest protection for any heritage site is defined by both the national and the Aragonese Cultural Heritage legislation as 'BIC' ('bien de interés cultural'-listed site of cultural interest) and includes two different categories, namely 'monuments' and Once a HE is listed, the municipality must follow article 41 of the LPCA by approving an urban plan ('Special Plan of Protection') to guarantee the compatibility of the conservation of its exceptional cultural heritage with other urban aspects, such as land use or energy efficiency. However, some small municipalities have very few technical and budgetary resources and, therefore, find it difficult to observe all these requirements. Besides, it might even lead to conflicts among their few inhabitants.
As a result, only 1 out of the 23 listed HEs of Teruel, Albarracín, has approved a 'Special Plan for the Protection of the HE' up to date. Since Cultural Heritage falls within the competency of the regional governments in Spain, the Directorate General of Cultural Heritage (Gobierno de Aragón) started an initiative in 2016 to support these small towns by elaborating exhaustive studies of several HEs. These studies are to become an essential part of the future municipal Special Plans of Protection of the historic ensembles.

Aims and scope of the studies
The main goal of these studies is to make inventories and determine their singularities, so they can become the base of comprehensive Special Plans, focused on their sustainable urban planning, and the conservation and protection of their heritage values. Therefore, they must comply with all urban planning and cultural heritage legal requirements.
A Special Plan aims to ensure the protection of the heritage ensemble (D.L. 1/2014, de 8 de julio, Texto Refundido de la Ley de Urbanismo de Aragón) 2 . It has to identify and analyse all types of interventions, the state of conservation of its buildings and urban tissue, and the use that might be compatible with the preservation of their heritage values. Then, it has to include a thorough inventory and bylaws for the subsequent Plan, too.
Historic ensembles are a very fragile sum of harmonic and distinguishable parts (buildings, public spaces, architectural features, rural and urban landscapes, etc.). They can transform as a whole when a single element or detail is inappropriate or stands out improperly.
Not only are the studies based on the aforementioned legal regulations but also they follow the guidelines of some widely recognised documents at a national and an international level, such as the 'National Plan for Traditional Architecture' (IPCE, 2015) or the ICOMOS Charter on the built vernacular heritage (ICOMOS, 1999). Thus, the specific objectives of the studies are: -To produce knowledge and accurate data by carrying out some detailed historical and archaeological research; -The analysis of the integration of the HE within potential growth areas; -The identification and protection of cultural, architectural, historical and landscape values, etc., which belong to the different layers of the HE. They make up its identity through a rigorous inventory and identification of vernacular construction techniques, typologies, and distinguishable units (neighbourhoods) within the urban and peri-urban tissue (implantation within the environment, borders, etc.); -The conditions and regulations to be met by any new constructions or interventions within the historic ensemble. -The survey of the road network to solve traffic conflicts and ensure as much accessibility as possible, without compromising the heritage values that have been identified and must be preserved as a priority; -The improvement and enhancement of both anthropised unbuilt spaces (streets, squares, parks, etcetera) and landscape by considering paving, street furniture, lighting and infrastructures; -The investigation of the potential of residential use and other complementary uses to revitalise the area, by safeguarding its urban, architectural and social components and intangible heritage (collective identity feeling, living traditions, craftsmanship, etc.); -The need to consider the urban tissue of the HE as a whole, by avoiding the assessment of the individual monumental buildings only; -To avoid facadism, the mere preservation of a set of empty urban landscapes, and other actions that can distort the traditional and vernacular elements of the municipality; -The involvement of local communities and the participation of as many stakeholders as possible.

Methodology
The study must follow four phases, to be carried out by a multidisciplinary team: The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Volume XLIV-M-1-2020, 2020 HERITAGE2020 (3DPast | RISK-Terra) International Conference, 9-12 September 2020, Valencia, Spain

Structure and content of the studies
In order to provide the municipalities with a document they can successfully shape into a forthcoming and binding Special Plan for Protection of the HE, the proposed framework for the studies replicates the general structure of urban plans (D. -Diagnosis: -Interpretation and conclusions of the analysis; -SWOT analysis (strengths-weaknesses-opportunitiesthreats).
-Aims and criteria of the proposals; -Description and justification of the specific proposals, taking into account the following aspects: -Planning of the HE; -Protection measures and criteria to adopt; -Proposals to improve the HE; -Identification of improper buildings, elements and spaces within the HE. -References.

Plans
The maps and plans shall adopt the most suitable scale to each map or graphic analysis in the study. Also, to facilitate their inclusion within the 'Special Plan', they will be the subject of some urban planning normalisation guidelines, as set by the regional regulations (Decreto 78/2017, de 23 de mayo, Norma Técnica de Planeamiento) 3 : Figure 2. The Study of Beceite proposed an extension of its buffer zone (in brown) to the north (Murría, 2018).
-Location map and scope of the study; BIC Historic Ensemble and its buffer zone; -Listed buildings and areas of interest: BIC, other buildings of interest according to architectural value, etc., areas with urban or archaeological values, etc. All these must be part of the inventory; -Historical evolution; -Current layout; -Built space (plots); -Defined areas, morphological units / neighbourhoods; The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Volume XLIV-M-1-2020, 2020 -Detailed land uses; -Heights of the built tissue; -Building typologies; -Public spaces; -Nested road network in relation to the entire municipality; -Characterisation of the unbuilt spaces: public and private; -Paving (identify traditional examples, recent ones, patterns, materials, integration of infrastructures…); -Infrastructures: electricity, lighting (overhead wires and/or underground network), water supply, sewage network, telecommunications; -State of conservation of public space, buildings and infrastructures, identifying potential ruins (according to law).
-Proposals -Delimitation of the listed HE and its buffer zone, and reasoned proposal for its modification, if appropriate. -Protection plans; -Identification of morphological units or neighbourhoods; -Public spaces and vacant areas. Guidelines for future interventions and design; -Road network (including car parks); -Priority areas (definition of most deteriorated areas); -Infrastructures, prioritising underground works for overhead wiring to avoid visual pollution.

Proposed/Draft Regulations
At this stage, the study may formulate some draft regulations, but they will only become binding once they are included in the Special Plan (D.L. 1/2014, de 8 de julio, Texto Refundido de la Ley de Urbanismo de Aragón) 2 .
-Guidelines and terminology, which should follow national or international charters (e.g. Burra Charter), for reference.
-Existing buildings: -Definition of the level or category of protection based on the inventory; -Types of interventions possible (must be compatible with its category of protection): -Conservation or 'minimal intervention'; -Maintenance; -Consolidation; -Restoration; -Refurbishment; -Retrofit; -Renovation; -Adaptation; -Reconstruction.
-Annex: It shall include an inventory to elaborate on the identification of traditional typologies and constructive techniques. It may include, but is not limited to: construction techniques, roofing systems, facades, windows, doors, eaves, paving, renderings, etc.
Besides, it is advisable to plan some specific draft regulations to apply to each of the identified morphological units (blocks, neighbourhoods, streets, squares, etc.). The need to harmonise with the traditional features identified in the typologies inventory is essential. Foreign elements and false imitations of materials and techniques shall not be allowed. Exceptional contemporary buildings might be possible, as long as they contribute to the ensemble's historic urban landscape and thus be passed by the Provincial Commission of Cultural Heritage.
-Plot regulations. Subdivision of historical plots is to be prohibited. -Protection of archaeological and palaeontological heritage.
The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Volume XLIV-M-1-2020, 2020

Inventory
This section needs to reflect the most remarkable buildings and spaces in the HE and their most significant features. Then, a level or category of protection must be assigned to each of them. The content must include general data of the building or site, its protection category (I, II, III), an extensive description, a location map, details about its use, state of conservation, the interventions allowed for this category of protection, photos, etc.

Results
The six studies shed light on the fragile situation of cultural heritage in small towns.
The teams (architects, historians, urban planners) identified some aspects that affect 100% of the case-studies: -The practitioners' lack of training in vernacular heritage leads to foreign construction techniques and physicochemical incompatibilities between materials; Since there are no bad intentions behind these interventions, the outcome of the studies should foster some awarenessraise campaigns and workshops, to involve all the stakeholders (owners, local governments, architects, builders, etc.); -Remote rural areas suffer from lesser infrastructures than cities. If there is any progress, heritage values may not be a priority; -Owners find too many disadvantages and restrictions because of living in a listed HE; -Depopulation is a major issue in rural areas. People prefer to live in larger towns, and only some spend time in the village over the weekends and holidays. As a result, ruins and lack of maintenance threaten their integrity; -Small changes could make a difference. The cooperation between stakeholders may diminish inadequate interventions and make them more sustainable. The outcome would be visible soon, and it would help build a stronger sense of belonging to a certain area; -Additional measures are necessary to guarantee the survival of HE. The adoption of respectful urban regeneration plans and the collaboration between public organisms to provide the local governments with comprehensive technical support is vital.

CONCLUSIONS
The initiative presented in this paper shows a scheme and set of actions to support the municipalities that manage listed HE in the process of development of the so-called 'Special Plans for the protection of historic ensembles' and to raise awareness among both policy-makers and local communities.
These case studies have built knowledge about the richness of cultural heritage and will help the discourse in areas where depopulation is a structural problem. Sometimes, their inhabitants do not know or even appreciate their vernacular heritage and seek foreign or picturesque solutions. Thus, it is common that spontaneous interventions end up damaging the HE values for good.
Engaging local communities, authorities, heritage and craftsmanship practitioners and other stakeholders is necessary for these studies and plans to succeed. In forthcoming studies, community involvement will continue to be the key to encourage local governments to take up the task of approving their Special Plans.
Actually, this could be the starting point of a creative impulse of social and economic measures and opportunities in times of crisis and scarce resources. The aim is to ensure living, sustainable towns where cultural heritage and its conservation may become an asset to fight against the challenge of the depopulation of remote rural areas. Finally, thank you to the local governments for their support and also to the people from the villages who have actively collaborated in the studies by opening their homes to the working teams. They have also provided precious oral information about their heritage and the problems they face because of living in a listed depopulated town.