**3. Results and Discussion**

Figure 8 allows a combined interpretation of the distribution of assets, both by their location into the different eight provinces of Andalusia, and by the sector of activity. Thus, a vertical reading of the graph provides an interpretation of the distribution of assets for each sector of activity through the eight provinces. When the graph is read horizontally, the distribution of assets into the different sectors can be observed for each territory. In addition, at the top of the graph and on the right side, the general distributions of the total number of assets that have been identified for each territory and for each activity sector are shown. Thus, regions and activities with special relevance and presence within the set of assets that are being considered can be identified, and then distribution trends can be observed through vertical and horizontal interpretations of the graph.

**Figure 8.** Distribution of assets simultaneously considering location and sector criteria.

At the same time, the different scales of the nodes in the graph enable identifying situations of special relevance. Examples of this are the high presence of assets linked to extraction activities in Almería and agroalimentary industries in Cádiz. The identification of these high presences is of high interest, and will derive in deeper studies in order to appreciate the circumstances behind these trends. Thus, in the case of Cádiz, by considering the scale criteria, it is possible to appreciate the significant presence of an immovable asset scale. When the set of assets is consulted, it is possible to identify a great number of windmills, which are the elements that make the presence of this activity sector so important within the distribution trends that are analyzed. Figure 9 shows this situation graphically. In addition, photographs of some examples of the identified windmills are included.

From a different point of view, the reutilization of this kind of assets for new activities is another aspect that is of the highest importance. Understanding the developed catalogue as a support tool for hierarchical multi-criteria structures, the identification and then the analysis of the reutilized assets represent key information.

In Figure 10, using a graph similar to the one used in Figure 8, the distribution of assets that simultaneously considers the criteria related to the location and the new uses is analyzed. At the top of the graph, the distribution of assets that is reutilized for each possible new use is shown, considering the assets located in every province. Thus, this trend represents the global distribution for this approach for the Autonomous Community of Andalusia. This analysis is of high interest, so it enables identifying the uses that have been able to activate new possibilities for assets that had lost their original function, and which needed a new one for their sustainable conservation. Consolidated examples of assets reused for new activities represent information of great value in order to establish appropriate strategies for the reutilization of this type of assets, providing examples of both good and bad practices.

**Figure 9.** Distribution of assets for the scale criterion applied to the agroindustry assets identified in the Province of Cádiz. The presence of windmills and some examples in Vejer de la Frontera: (**a**) and (**b**) windmills at "Loma de la Buenavista"; (**c**) windmills that neighbor San José; (**d**) windmill "la Cruz de Conil".

**Figure 10.** Distribution of assets simultaneously considering location and the new use when it exists.

In addition, it is possible to make a similar horizontal interpretation of the graph for each province. This enables appreciating the particular trends within each territory and identifying the most relevant new uses in each case.

When Figure 10 is interpreted vertically, it is possible to appreciate the presence of the assets identified for each new use within every particular territory. This enables identifying the special relevance of some sectors of activity in particular territories. For example, in the case of the use identified as "administrative and office", the graph shows the especially significant importance of the Province of Sevilla with regard to this use. At the same time, for the uses with highest presence, which are the ones identified as "industrial heritage informative" and "social and cultural", the graph shows trends with more balanced presence distributions in each territory, but it is also possible to identify the most significant provinces in each case.

On the right side of the graph, the total reutilization of assets observed in each territory is shown. This global analysis does not take into account the specific nature of the new activities, but rather

considers the total number of assets reused through the different new uses in each province. Both the number of assets reused in each territory and the percentage of them within the total number of reused assets in Andalusia are indicated. Furthermore, the amount of reused assets in each territory is related to the total number of assets considered in the catalogue for the corresponding province. Thus, for each territory, the blue bar corresponds to the reused assets, and the orange bar corresponds to the ones that have not been recovered for new activities. Within each orange bar in the graph, the percentage of reused and not reused assets for each territory is indicated, using blue and orange text respectively in order to add clarity.

Furthermore, as in the graph shown in Figure 8, the size of the nodes makes a fast and easy identification of special and relevant situations possible, such as the previously mentioned presence of the use that is denominated as "administrative and offices" in the Province of Sevilla, or the significant number of assets dedicated to industrial activities in the Province of Cádiz. The identification of these and other high presence situations within the graph enable proposing and defining new analyses when necessary.

Since information about the reutilization of these assets for new activities is important, both as a sustainable strategy for their conservation and as support for the multi-criteria decision structures included in the global methodology developed by the authors [1,19], further analyses are exposed in order to show the potential of the catalogue as a useful and flexible tool.

Figures 11 and 12 propose new approaches by considering simultaneously three different categories of criteria: location, new uses, and scale. Figure 10 identifies "industrial informative heritage" and "social and cultural" as the uses with higher number of assets. On a second level, it is possible to identify three uses: "administrative and offices", "educational and research", and "monument/sculpture". These uses of special presence represent the most consolidated reuse strategies of this typology in Andalusia, and analyzing the possible influence of characteristics such as the scale of the reused assets represents a very interesting approach. Thus, Figures 11 and 12 incorporate a new criterion into the analysis shown in Figure 10, the scale of the corresponding assets, in order to identify possible relations between the activities established and the scale of the affected assets.

**Figure 11.** Distribution of assets within the two new uses with the highest number of assets and also considering the location and the scale criteria.

**Figure 12.** Distribution of assets within the new uses with a significant number of assets and considering the location and the scale criteria.

At the top of Figure 11, the distribution of assets through the eight provinces of Andalusia and the presence in each case of the scale categories considered into the catalogue are shown for the use "industrial heritage informative". At the bottom of Figure 11, the same approach is applied to the assets corresponding to the use "social and cultural". In both cases, a representation of the total distribution of scales for the analyzed use is shown on the right side of the figure. The same approach is applied in Figure 12 to the other three analyzed uses.

Observing both figures, it is possible to appreciate some trends of interest. Firstly, it can be noticed that the "territorial infrastructure" scale does not have presence. This highlights the greater difficulties that the assets of this scale present in terms of reuse for new activities. Regarding the use of "industrial heritage information", the other four scale criteria that are considered in the catalogue have representation, and in most of the cases, in several different territories. This heterogeneity is due to the nature and the objectives of this possible use, whose main purpose is not only the conservation, but also the dissemination and promotion of the concerned asset and its heritage values. Thus, it is not so much the scale demanded by the new use, but the scale of the original asset itself that persists, since the scale itself is a distinctive feature, and a characteristic of the value that must be preserved and shown. In the other cases, it is possible to identify a clear prevalence of some scales over others.

In the case of the use named "social and cultural", two scales have a clear predominance without signs of a significant preference for either one of them. Thus, both the "immovable asset" and the "system or set of buildings" scales emerge as the main alternatives for this use. In addition, two examples of "landscape or area" scale appear. This is due to isolated situations derived from the classification guidelines established for the construction of the catalogue [1]. Industrial landscapes and areas represent dimensions clearly different from other scales such as industrial facilities composed by a set of buildings, so this kind of elements must be identified as such. However, other criteria of the classification structure applied into the catalogue may affect only some of the recognizable single elements that are included within that landscape or area. The reuse of some of the elements while the others are abandoned, or the legal protection only of some of them, are examples of this situation. This way, the general guideline applied in the catalogue is the identification of the landscape or area scale as an asset into the catalogue, and then the identification of those elements that have special classification circumstances through the classification criteria structure as new and different assets. Due to this, while each one of the elements that are included within that greater scale asset usually present a single new use (in cases in which they have been recovered for a new activity), the corresponding asset of the greater scale will consider the uses identified with all of them, although only one of them is in fact the use of that landscape or area. Thus, the presence of assets with a scale of landscape or area for social and cultural use is a consequence of the limitations of the classification criteria structure, not a real relation between that scale and that use.

In the case of "administrative and offices" use, a certain preference for the scale named "system or set of buildings" is shown, but a clear trend is not able to point out the relation between the needs of the use and the characteristics of the scale criterion. Furthermore, regarding "educational and research" use, the preference for this scale is very significant. This is because in this case, the relation between the needs of the use and the distinctive characteristics of each scale exists, since a main need of educational centers is playgrounds, as spaces that can be disposed between the buildings and elements of some typical industrial facilities layouts. These kinds of conclusions are of great value when multi-criteria decision structures for the selection of the most compatible new uses are built [1,19].

Finally, the third graph included in Figure 12 shows the scales linked to "monument or sculpture" use. This use is mainly focused on chimneys and other elements, such as furnaces, which are inhabitable due to their scale. Thus, this kind of asset does not have the capacity to accommodate any kind of new uses. Nevertheless, they are industrial elements of interest, so they must be identified, classified, and protected. In Figure 12, it is possible to appreciate the significant presence of this scale, but also the "immovable asset" scale has presence, especially in the province of Cádiz. This is due to the significant presence of windmills in this territory, which was previously exposed and also graphically illustrated in Figure 9.

New criteria added to the classification criteria structure of the catalogue can be also analyzed, both from approaches focused on their own information and combined with other criteria. As exposed before in the section "relation with [the] local population", these criteria try to show the possible synergies between each asset and the nearest population centers. Two main aspects affect this relation: the population of the corresponding village, town, or city, and the road communication and general accessibility to the asset from the corresponding population center. Both aspects are important when new uses are proposed, but a connection between both elements is the key issue. A large population provides potential users with the new activities, but if there is no real relation between the asset and the population center, its size will not be relevant. This idea is graphically explained in Figure 6. Thus, six relation criteria categories are defined, which can be understood as seven when the special role of "province capital" exists. Firstly, Figure 13 analyses the size of the nearest population centers for each asset of the catalogue.

**Figure 13.** Distribution of assets within classification categories focused on the relationships with population centers by considering the number of inhabitants.

As exposed in Figure 6, three main situations can be distinguished by considering the relation between the asset and the nearest center of population; rural locations, semi-rural locations, and city or urban locations. Within urban contexts, four subcategories are defined (town, small city, medium city, and big city), making it possible to distinguish different sizes. Size is a key aspect to understand how a city works. Road and communication systems, infrastructures, and services are examples of aspects with different dimensions and complexity levels according to the type of city. However, rural and semi-rural locations have no relation to the size of the nearest population centers. In that sense, Figure 13 analyses the different sizes identified for the assets classified within each one of the categories that were considered.

It is possible to appreciate how population centers that are linked to assets with rural and semi-rural locations have in many cases significant sizes, which are similar to the ones identified for small and medium cities. On the left side of Figure 13, a zoom of that part of the graph is made in order to appreciate these situations more easily. The real potential synergies with population centers when a possible new activity is evaluated for an asset will be conditioned by aspects such as the size of those villages, towns, and cities, so these approaches are of interest when reutilization studies are being developed. On the other hand, Figure 13 reveals how most of the assets that have been identified for the category of big cities are located in province capitals, although there are a few located in some of the other big cities identified in Table 2. Despite the size of the cities, their social and administrative roles are also important, so not only the size is relevant, but also being the capital of a region has a great value, and can make it easier to develop these kinds of reuse projects.

In that sense, Figure 14 tries to identify the relations between these location categories and the presence of reuse initiatives. As it is shown, there is a great leap in this aspect between rural and semi-rural locations and the rest of the categories, which are associated with urban contexts. This highlights the influence of context circumstances for the success of reuse actions, but the identification of those examples that exists in rural and semi-rural environments and the strategies applied within them are also interesting.

Within the urban categories, the highest reuse values are identified for bigger city sizes. Thus, medium and large cities are the categories with a greater percentage of assets reused for new activities. In the case of big cities, the role as a province capital is able to increase this percentage, but not in a really significant way. It is also interesting that medium-size cities obtain a major reuse percentage. This can be due to the more aggressive urban growth processes that usually happen in big cities and which significantly modify the uses and the land value, which are aspects that make the conservation of old industrial facilities very complicated from a business viewpoint. In addition, the bigger the city is, the more difficult the feelings of belonging to the social history and tradition of the place among the population. These feelings are able to contribute to the conservation of the elements of this typology in a key way, or not.

**Figure 14.** Assets reused and not reused for each classification category referred to the relation with the local population. New uses are of a general nature.

#### **4. Conclusions**

The analyses shown in this work are just some of the possible approaches that the developed catalogue allows, but they are considered as representative of the possibilities and potential that these kinds of tools can have in the study, promotion, management, and protection of the assets of the industrial heritage. The results obtained are considered of interest for all of these tasks.

The importance of the incorporation of sufficiently complete criteria structures to the cataloguing initiatives is a key aspect for their usefulness. Industrial heritage cannot be promoted or studied through simple compilations of assets. Their nature and main characteristics must be ordered through an appropriate classification criteria structure that is able to allow both the characterization of the typology and the contextualization of each asset within the sample. This work defines and proposes a full criteria structure for the classification of this type of assets. The main aspects to be taken into account when industrial assets are analyzed are studied through different groups of criteria that are focused on each one of those key aspects. Application guidelines are also given in those cases in which more doubts can rise, what is critical if the catalogue wants to be understood as a real tool.

Thus, the authors consider the developed catalogue as a useful tool in the field of the industrial heritage, both in the international context as a methodological approach and in the particular context of Spain as a tool that represents a significant progress from the previous situation. This usefulness is highlighted in the other works of the authors in which the catalogue and the criteria structure applied to all of them is the substrate in which other methodologies are based [1,19]. Indeed, the new criteria have been included in the structure of the catalogue as a response to the needs that have been identified during its use.

Regarding further developments of the catalogue, and particularly with regard to the actualization of the sample in other territories and the continue revision of the full set of assets considered, the most valuable strategy is a collaborative growth of the catalogue. The authors have previous experiences in the collaborative cataloguing of industrial assets within a university context with positive results. Thus, transforming the catalogue developed in an open tool represents an interesting challenge not only for social promotion of the industrial heritage in Spain, but also as a growth strategy of the sample. Probably, a collaborative identification of assets is the only sustainable and successful strategy for the development of a complete catalogue of this typology in such a large territory as Spain. By availing the knowledge of the potential users of the catalogue located throughout the national territory, which are who know the best examples in their territories, it would be possible to identify and include a large number of assets of great value.

**Author Contributions:** Conceptualization, J.C. and M.A.S.; methodology, J.C. and M.A.S.; software, J.C. and A.G.-D.; validation, J.C., A.G.-D., L.S. and M.A.S.; formal analysis, J.C., A.G.-D. and L.S.; investigation, J.C. and A.G.-D., L.S. and M.A.S.; resources, J.C., L.S. and M.A.S.; data curation, J.C., A.G.-D., L.S. and M.A.S.; writing—original draft preparation, J.C. and A.G.-D.; writing—review and editing, J.C., A.G.-D., L.S. and M.A.S.; visualization, J.C. and A.G.-D.; supervision, L.S. and M.A.S.; project administration, J.C. and M.A.S.; funding acquisition, J.C., L.S. and M.A.S.

**Funding:** This research was partly funded by the Manufacturing Engineering Society (http://www.sif-mes.org/) through a mobility grant given to the first author. This research period was developed in the University of Malaga during 2016 and supervised by Professor Sevilla and Professor Sebastián. The results obtained during this research stay represent a significant part of the support data used in this work.

**Conflicts of Interest:** The authors declare no conflict of interest.
