Research on Living Conservation Strategies for the Ming-Guangwu Great Wall Based on the Grey Relational Analysis Model

Abstract

The Great Wall of China is a cultural monument of profound historical significance and a testament to the evolution of various historical periods. As a living heritage, it holds exceptional value. However, due to inadequate protection measures in recent years, numerous sections of the Great Wall have been subject to continuous degradation. While damage to its main structural components and explicit heritage elements has been widely acknowledged, the more critical issue lies in the ambiguous recognition and insufficient safeguarding of its implicit heritage elements. This study explores the composition and classification of protective elements associated with the Great Wall, proposing a framework that emphasizes the dual safeguarding of both its tangible structures and intangible cultural significance. Employing big data collection through search engine optimization (SEO) techniques and questionnaire surveys, this research analyzes recent trends in the prioritization of heritage conservation efforts related to the Great Wall. Furthermore, by constructing a mathematical model based on the “grey relational analysis” method, the study classifies and stratifies various heritage elements to highlight the Wall’s core values and propose targeted protection strategies. The findings reveal that (1) certain regions possess considerable development potential and can be restored and planned as cultural tourism destinations; (2) conservation efforts should prioritize material restoration while preserving the intrinsic spiritual and cultural values; (3) a living heritage transmission strategy should underpin the overall protection framework. Ultimately, the study establishes a classification and grading system for conservation elements centered on the sustainable development of the Great Wall heritage. By concretely mapping the concept of living heritage protection onto the various protective elements of the Great Wall, this research offers valuable insights and recommendations for enhancing conservation practices.

1. Introduction

As a significant component of linear cultural heritage (LCH), the Great Wall bears witness to and extends through the historical trajectory of China, embodying the cultural integration of various ethnic groups [1]. Since the promulgation of the Master Plan for the Protection of the Great Wall (2018–2035) by the Chinese government [2], the conservation of the Great Wall has entered an unprecedented phase of development. The United Nations Educational, Scientific and Cultural Organization (UNESCO, Paris, France), in its State of Conservation Report (2019), affirmed China’s efforts in safeguarding the Great Wall and emphasized the importance of conducting Heritage Impact Assessments (HIAs) prior to the implementation of development projects, so as to minimize adverse impacts on heritage sites [3]. Research on the holistic protection of heritage and its surrounding context has become a critical focus within international heritage conservation discourse. Foundational documents such as the Nara Document on Authenticity (1994) and the Venice Charter (1964) advocate for the consideration of historical context, natural environment, and other key factors in heritage preservation, promoting the expansion of conservation objectives to include the integrity and diversity of the site’s broader environment. Scholars in the field have also called for an expanded interpretation of cultural heritage that includes the protection of its unique cultural attributes and spatial structures [4,5]. Linear Cultural Heritage refers to heritage linked by cultural routes and characterized by linear or elongated spatial features. These heritage types integrate cultural resources within geographic space and are marked by extensive spatial coverage and rich biocultural diversity [6]. Notable LCH-related conservation studies have focused on heritage canals [7,8,9,10], industrial heritage [11,12,13], ancient trails [14,15], and the Great Wall [16,17,18,19,20]. Unlike discrete or centralized architectural heritage, LCH represents the result of interactions between human settlements, cultural heritage, and the surrounding environment. Over time, these interactions evolve alongside local cultural identities and community values, rendering LCH particularly sensitive to social and environmental change. Currently, the sustainable development of the Great Wall faces numerous challenges, including landscape fragmentation, community development pressures, tourism expansion, and ineffective heritage management. The lack of dynamic and integrated conservation strategies has hindered effective responses to these challenges. It is widely recognized that the dynamic relationship between the Great Wall and contemporary socio-economic development is diminishing. Therefore, there is an urgent need to explore more flexible and adaptive management approaches to LCH areas from a perspective that integrates heritage conservation with sustainability. Such approaches would enable the preservation of the unique characteristics of different heritage regions while accommodating the ongoing processes of change, development, and renewal in the contemporary world [5].

The concept of the “Living Heritage Approach” (LHP) was first proposed by ICCROM, Rome, Italy in 2009. Within this framework, living heritage is defined as heritage that retains and continues to fulfill its original function in the present day [21]. From a functionalist perspective, living heritage is understood as a distinct category that contrasts with static heritage. Existing research on LHP has been applied to various domains, including historical urban water systems [22], archaeological parks [23,24,25], traditional villages [26,27,28], and historic streets and alleys [29]. In the field of intangible cultural heritage studies, the term “living” is often used interchangeably with “living protection” or “living transformation” (huotaihua), emphasizing not only the preservation of the original attributes of heritage but also its active adaptation to contemporary societal needs. The core of this approach lies in the concept of revitalized utilization, which seeks to promote sustainable development through the scientifically informed preservation and presentation of heritage, while also facilitating regional economic benefits through rational and coordinated use. This process, referred to as “living transformation,” ultimately aims to achieve conservation-led utilization and foster long-term socio-economic synergies at the regional level [30]. Based on this conceptual evolution, living heritage can be broadly categorized into two types: (1) continuous living heritage that maintains its original function, and (2) transformed heritage that has lost its initial function but is repurposed to serve new roles. In the case of the Great Wall—which no longer serves its original defensive function—it becomes necessary to reassign new roles such as national parks, museums, or thematic cultural parks. By redefining or adapting its functional attributes, a renewed relationship with local communities can be established. This enables a holistic and dynamic continuation of the site’s vitality and cultural relevance [31,32].

The “Cultural Iceberg Theory” was first introduced by Edward T. Hall in the 1960s in his seminal work Beyond Culture. Hall conceptualized culture as comprising both visible and invisible components, likening it to an iceberg. The visible portion above the waterline represents explicit culture, which is embedded in tangible and material entities. In contrast, the submerged nine-tenths of the iceberg represents implicit culture, which exists beyond conscious awareness and constitutes the deeper, core elements that influence and shape human behaviors and beliefs [33]. In the context of Great Wall conservation, this theory provides a valuable framework for distinguishing between explicit elements—the visible, physical aspects of the heritage—and implicit elements—the intangible, value-laden components. Explicit elements include the tangible physical features of the Great Wall, such as its architectural style, materials, and spatial configuration. Implicit elements, on the other hand, are not physically manifested but exert significant influence over the form and perception of explicit features. These include cultural values, symbolic meanings, historical narratives, and traditional craftsmanship associated with the Wall [26]. In recent years, international scholarship on the conservation of the Great Wall has increasingly focused on identifying and integrating both the cultural landscape characteristics and the natural–cultural value continuum. For example, researchers have applied the Landscape Character Assessment (LCA) methodology to systematically identify and classify the cultural landscape features within the Great Wall heritage zones. These studies have revealed a high degree of coupling between the Great Wall and its surrounding natural environment, underscoring the necessity of integrating natural and cultural elements within conservation planning to achieve holistic protection and management [5]. Additionally, advances in digital conservation technologies have played a pivotal role in enhancing the protection of the Great Wall. These include the use of digital documentation tools to capture detailed information about conservation elements; high-precision 3D laser scanning to model structural deformations and enable virtual restoration; and the integration of Building Information Modeling (BIM) with Geographic Information Systems (GIS) to establish comprehensive information management platforms. Such technologies support life-cycle conservation strategies and provide critical decision-making tools for heritage management [6].

By designing and administering surveys on Great Wall conservation elements and analyzing relevant research trend data, this study identifies a comprehensive set of conservation indicators based on the Cultural Iceberg Theory. Utilizing the Grey Relational Analysis (GRA) method, both qualitative and quantitative analyses are conducted on the identified indicators. This enables the construction of a hierarchical classification system for conservation elements. Building upon this framework, and informed by the Living Heritage Approach, the study proposes practical strategies and recommendations for the dynamic transmission and conservation of the Great Wall as a living heritage. This methodological approach is equally applicable to the conservation of other types of linear heritage, such as canals, industrial sites, and traditional villages [34]. Unlike the Great Wall, traditional villages inherently qualify as living heritage due to their ongoing cultural and social functions. However, under the pressures of rapid urbanization, many traditional villages are disappearing at an alarming rate. Beyond the issues of depopulation and the destruction of visible, material elements, the collapse of the internal core of intangible cultural values—i.e., the implicit elements—has emerged as an even more critical threat to their long-term survival.

2. Data Sources and Research Methods

2.1. Study Area

The Ming Guangwu section of the Great Wall is located in Shanxi Province, within Shanyin County of Shuozhou City (Figure 1). It extends from Xinguangwu Village to Baicaokou Village in Daixian County, with a total length of 7.2 km. Currently, the site retains 38 watchtowers and 27 beacon towers [35]. The selected study area encompasses Watchtowers No. 9 to No. 13 along the Guangwu third segment, spanning approximately 1 km (Figure 2).

Geographically, the Ming Guangwu Great Wall lies to the east of Yanmen Pass, overlooks the old town of Ningwu to the west, connects to Mount Wutai in the south, and extends northward to the Yungang Grottoes (Figure 3). The region is characterized by a temperate continental monsoon climate, with an average annual temperature ranging from 3 °C to 14 °C and significant diurnal temperature variation. Annual precipitation averages between 400 and 650 mm [36]. Influenced by this climate, the area exhibits lush and vigorous vegetation during the summer—predominantly temperate deciduous broad-leaved forests—offering striking natural scenery, while in winter, the vegetation withers and declines significantly [18]. Therefore, vegetation conservation in this area should prioritize the use of native plant species. In addition, the implementation and selection of restoration measures must take into account local climatic conditions, particularly winter hardiness and susceptibility to desiccation and cracking.

The Ming Guangwu section of the Great Wall was originally constructed during the Warring States period; however, due to the passage of time and successive dynastic changes, much of the original structure suffered significant damage. According to historical records, a large-scale reconstruction was undertaken in the 7th year of the Hongwu reign of the Ming Dynasty (1374 CE), followed by additional reinforcement works completed in the 33rd year of the Wanli reign (1605 CE). The surveyed area, extending from Xinguangwu to Motianling, is part of the inner Ming Great Wall. This segment features masonry construction, with the wall enclosed in bricks and stone. Historically, it served as a crucial military defense line along the frontier, playing a significant role in guarding against external threats and securing the border [6,18].

Regional Overview: The surveyed area comprises a semi-developed section of the Great Wall ruins, with limited infrastructure. Currently, the only constructed feature is a landscape walkway built along the original “official road” (guandao). In 2016, relevant authorities conducted a protective restoration of the collapsed landmark structure known as the “Moon Gate.” Utilizing original image archives and modern 3D modeling and printing technologies, new bricks were employed to reinforce the remaining central pillar (“single column”), and a foundation platform was reconstructed following the original watchtower layout. The remaining portions of the wall have been left untouched, preserving their original historical appearance and material integrity. As a result, the primary visitor area extends from Watchtower No. 9 to Watchtower No. 10 (Moon Gate). Visitor traffic is significantly influenced by weather conditions, with most tourists being passersby en route to the nearby Yanmenguan Scenic Area. The average flow is estimated at 15–20 visitors per hour, based on the number of individuals arriving at the Moon Gate. Currently, the study area lacks formal management and planning. Infrastructure is minimal, consisting of a small shop run by a local resident, basic fire safety and sanitation facilities, and no established management system or economic return. However, this region lies along the “Great Wall No. 1 Scenic Road” and is situated within the spatial framework of the regional Great Wall development strategy, which follows the general structure of “one belt, three sections, six zones, and multiple nodes.”

Survey Findings: 1. Heritage Site Integrity: The primary structure of the site is generally well-preserved, maintaining its original form and linear alignment. The wall’s overall morphology and structural integrity remain intact; however, the surface bricks and stones have suffered significant erosion, with only limited portions remaining on the top of the wall. Ancillary architectural elements of the Great Wall, including watchtowers, beacon towers, and bunkers, are well-preserved. In addition, the ancient trail is largely intact, and a scenic route has already been constructed along it. 2. Environmental Context: The site is surrounded by mountains on all sides, with the Great Wall constructed in alignment with the natural topography, resulting in considerable elevation changes. The surrounding area is rich in plant species, characterized by vibrant colors and dense vegetation. Geographically, the site is adjacent to the G55 Erguang Expressway, offering convenient transportation access. It also lies along the designated Great Wall scenic highway, indicating potential for integrated regional development (Figure 4). Overall, the surveyed area demonstrates well-preserved physical conditions and possesses notable conservation, aesthetic, and tourism value. These factors indicate a high level of feasibility for the protection and development of this section of the Great Wall heritage.

2.2. Research Methods

This study first employs a questionnaire-based survey method to develop a database encompassing the current conservation status, development, planning, and key protection elements within the Ming Guangwu section of the Great Wall. Subsequently, SEO-based big data collection techniques are utilized to gather information on current research trends and hot topics related to Great Wall conservation. Drawing upon the Cultural Iceberg Theory, the collected data—both from the questionnaire and big data sources—is categorized into explicit and implicit heritage elements. This classification facilitates the identification and refinement of key conservation indicators. Thereafter, the Grey Relational Analysis (GRA) method is applied to normalize and integrate the disparate data sets, thereby establishing degrees of association among them. Selected factors are subjected to both qualitative and quantitative evaluation to assess the significance and priority of conservation elements. Based on this analytical framework, a classification and evaluation system for Great Wall conservation elements is constructed. Building upon the resulting system, and integrating principles from the Living Heritage Approach, this study proposes targeted protection strategies and practical recommendations aimed at sustaining the living transmission of the Great Wall’s cultural and historical significance. This combined methodological approach can also be applied to the identification and conservation of protection elements in other types of linear heritage and traditional villages (Figure 5).

2.2.1. Questionnaire Survey

Between 2023 and 2024, two rounds of field surveys were conducted annually in the Ming Guangwu Great Wall area using structured questionnaires. A total of 120 individuals participated in the survey, including local tourists (81 respondents), residents (21 respondents), village officials (5 respondents), vendors (3 respondents), and researchers or experts (10 respondents). The questionnaire comprised three major categories of questions: (1) Ontological Conservation—focusing on opinions and perspectives regarding the physical preservation of the Great Wall; (2) Identification of Conservation Elements—investigating respondents’ recognition and classification of key conservation elements; and (3) Development Planning—gathering suggestions and viewpoints concerning the future development and planning of the Great Wall. The section on the identification and classification of key conservation elements was completed by respondents with guidance and assistance provided by relevant team members to ensure accuracy and consistency in interpretation.

2.2.2. Search Engine Optimization (SEO)

SEO can be utilized to identify terms that are strongly associated with specific target keywords, providing a direct reflection of research popularity and emerging hotspots. The resulting data is both timely and reflective of current trends. However, SEO-based analysis also presents certain limitations. The datasets are often vast and interdisciplinary in nature, necessitating manual filtering and refinement. Additionally, the data tends to be short-lived, with limited temporal scope, which may affect long-term analytical validity.

2.2.3. Grey Relational Analysis (GRA)

Grey Relational Analysis (GRA) is an effective method for analyzing the relationships among multiple variables within a system characterized by uncertainty or incomplete information. In a grey system, the degree of association between a reference indicator and various influencing factors is evaluated and ranked to determine the strength of their interrelationships—referred to as the grey relational degree [37]. This enables researchers to identify trends and perform quantitative assessments across complex, multivariable scenarios. In this study, the GRA mathematical model was applied to examine the correlation between implicit elements and the overall conservation value of the Great Wall heritage. By calculating the grey relational degrees for each implicit element, their relative importance could be visualized and systematically compared. These results serve as a critical foundation for identifying key focus areas in the development of strategies for the living conservation of the Great Wall, ensuring that preservation efforts are both evidence-based and strategically prioritized [38].

(1)

Data normalization:

$$F_n={\displaystyle \frac{f\left(x_n\right)-f\left(\min \right)}{f\left(\max \right)-f\left(\min \right)}}\left[0-1\right]$$

where $f\left(x_n\right)$ represents the original value of the n-th data point, and $f\left(\min \right)$ and $f\left(\max \right)$ denote the minimum and maximum values within the dataset, respectively.

(2)

Determination of the minimum and maximum absolute differences between reference and comparative sequences:

$$a=\min \left|x_0\left(k\right)-x_i\left(k\right)\right|,\forall i,k$$

$$b=\max \left|x_0\left(k\right)-x_i\left(k\right)\right|,\forall i,k$$

where $x_o\left(k\right)$ is the value of the k-th element in the reference sequence $x_0=\left\{x_0\left(1\right),x_0\left(2\right)\dots x_0\left(n\right)\right\}$, and $x_i\left(k\right)$ is the corresponding value in the comparison sequence $x_i=\left\{x_i\left(1\right),x_i\left(2\right)\dots x_i\left(n\right)\right\}$.

(3)

Computation of the Grey Relational Coefficient:

$$\gamma x_0\left(k\right),x_i\left(k\right)={\displaystyle \frac{a+\rho b}{\left|x_0\left(k\right)-x_i\left(k\right)\right|+\rho b}}$$

where $x_i\left(k\right)$ represents the grey relational coefficient between the reference and comparison sequences at point k, and rho in [0,1] is the distinguishing coefficient, generally set at 0.5.

(4)

Calculation of the Grey Relational Degree:

$$\gamma \left(x_0,x_i\right)={\displaystyle \frac{{\displaystyle {\sum }_{k=1}^n\gamma \left(x_0\left(k\right),x_i\left(k\right)\right)}}{n}}$$

where gamma $i$ denotes the grey relational degree of sequence $x_i$ relative to the reference sequence $x_0$, reflecting the overall correlation between the implicit factor and the reference target.

2.3. Data Source

The data and materials used in this paper mainly come from the following methods:

(1)

Field Investigation: The research team conducted an on-site investigation of the Ming Guangwu section of the Great Wall. Data were collected through questionnaires, photographic documentation of the current condition, drone aerial imagery, and interviews with local villagers. These efforts aimed to gather comprehensive information regarding the heritage conservation elements and future protection and development strategies of the area.

(2)

Literature materials: A wide range of sources were consulted and collected through platforms such as the internet, CNKI (China National Knowledge Infrastructure), and other academic databases. The data collection covered a wide range of sources, including but not limited to Wanfang Data, VIP Database, MDPI, and Google Scholar. The collected materials included, but were not limited to, scholarly articles, professional monographs, county chronicles, Great Wall atlases, and relevant policies and regulations concerning the conservation of the Great Wall.

(3)

Data Acquisition: Base map data used in this study were obtained from Google Earth, OpenCycleMap, and Baidu Maps. Satellite imagery was sourced from Bigemap GIS and Bigemap Pro. Data for the evaluation framework were primarily collected from CNKI. Analytical and processing tasks were performed using SPSS25.0, ArcGIS 10.8, and other supporting software tools.

3. Results and Analysis

3.1. Establishment of the Dictionary of Conservation Elements for the Great Wall Heritage

3.1.1. Obtaining Protective Elements

A questionnaire survey was employed to collect data on the conservation elements of the Great Wall. A total of 120 questionnaires were distributed, of which 112 valid responses were retained after excluding incomplete or invalid submissions. From these responses, 55 distinct terms related to the conservation of the Great Wall were extracted. Among them, issues concerning physical damage and restoration were mentioned with the highest frequency, totaling 68 references. In contrast, intangible and spiritual aspects of conservation were cited 51 times. Content related to the functional transformation of the Great Wall in the context of contemporary society received comparatively fewer mentions. This discrepancy is primarily attributed to the fact that the survey was conducted at a site yet to undergo formal conservation planning, where evident damage and structural collapse dominated public attention. As a result, most participants focused on restoration of the physical structure, while only a minority expressed views regarding future development strategies for the Wall. Based on the collected data, the conservation elements were ultimately classified into five main categories: natural, environmental, economic, architectural, and protective components [39].

To ensure the comprehensiveness and professional rigor of the Great Wall conservation elements, in addition to the questionnaire survey, SEO data collection methods were employed. Relevant literature and data were integrated using tools such as the 147 Data Collector, 5118 Big Data Platform, and Diandian Webmaster Tools. Using “Great Wall heritage” and “Great Wall heritage conservation” as primary keywords, relevant long-tail keywords were extracted to identify current conservation hotspots (

Table 1. Data sheet of Great Wall protection elements.

Data Collection Method	Preprocessing Data Volume	Data Related Keywords
147 Data Collector	150	576
5118 Big Data Platform	29,492	270
Relevant literature on CNKI	157	95

). A total of 941 related keywords were retrieved. Following the classification framework of the questionnaire survey, which categorizes elements into five major groups—natural, environmental, economic, architectural, and conservation-related—these keywords were filtered to select 83 high-frequency keywords, representing 83 key conservation elements (

Table 2. Elements of Great Wall heritage protection.

Classification	Primary-Level Explicit Elements	Secondary-Level Explicit Elements	Implicit Elements
natural	natural conditions	Topography and Geomorphology, Climatic Environment, Altitude Variation, Soil and Vegetation	Natural Value (f2), Historical Value (f5), Historical Environment (f8), Political Environment (f9), Development Planning (f11)
	geographic location	Site Selection Characteristics, Environmental Factors, Geomantic (Feng Shui) Factors	Natural Value (f2), Historical Value (f5), Historical Environment (f8), Political Environment (f9), Development Planning (f11), Regional Culture (f14), Ethnic Culture (f15), Religious Belief (f16)
economic	activation forms	National Park, Tourist Attraction, Cultural Landscape, Museum	Cultural Value (f1), Natural Value (f2), Spiritual Value (f3), Functional Value (f4), Cultural Transmission (f6), Collective Memory (f7), Political Environment (f9), Development Planning (f11), Development Models (f12), Great Wall Culture (f13), Regional Culture (f14), Ethnic Culture (f15), Religious Belief (f16)
	industrial types	Tourism Industry, Commercial Sector, Service Industry, Agricultural Sector	Cultural Value (f1), Functional Value (f4), Historical Environment (f8), Political Environment (f9), Development Planning (f11), Development Models (f12), Regional Culture (f14)
	cultural development	Cultural and Creative Products	Cultural Value (f1), Spiritual Value (f3), Functional Value (f4), Cultural Transmission (f6), Collective Memory (f7), Great Wall Culture (f13), Regional Culture (f14), Ethnic Culture (f15), Religious Belief (f16)
environmental	public environment	Natural Landscape, Surrounding Villages, Built Environment	Natural Value (f2), Functional Value (f4), Historical Environment (f8), Development Planning (f11), Regional Culture (f14)
	basic infrastructure	Transportation Modes, Logistical Modes, Community Relations, Lifestyle, Language and Script, Dietary Characteristics	Cultural Value (f1), Spiritual Value (f3), Functional Value (f4), Historical Value (f5), Cultural Transmission (f6), Collective Memory (f7), Development Planning (f11), Regional Culture (f14), Ethnic Culture (f15), Religious Belief (f16)
architectural	architectural composition	Architectural Form, Construction Techniques, Texture and Ornamentation, Building Envelope, Epigraphic Murals, Architectural Style, Structural Composition, Building Materials, Architectural Color Scheme	Cultural Value (f1), Spiritual Value (f3), Functional Value (f4), Historical Value (f5), Cultural Transmission (f6), Collective Memory (f7), Historical Environment (f8), Traditional Craftsmanship (f10), Regional Culture (f14), Ethnic Culture (f15), Religious Belief (f16)
	architectural characteristics	Religious Architecture, Political Architecture, Defensive Architecture, Military Architecture, Landscape Architecture, Public Architecture, Landmark Architecture, Exhibition Architecture	Cultural Value (f1), Natural Value (f2), Spiritual Value (f3), Functional Value (f4), Historical Value (f5), Cultural Transmission (f6), Collective Memory (f7), Historical Environment (f8), Development Planning (f11), Development Models (f12)
	architectural morphology	Spatial Composition, Spatial Layout, Morphological Evolution, Route Orientation, Quantitative Scale, Distribution Characteristics, Street Configuration	Functional Value (f4), Collective Memory (f7), Historical Environment (f8), Political Environment (f9), Regional Culture (f14), Ethnic Culture (f15), Religious Belief (f16)
protective	damage and deterioration	Natural Weathering, Anthropogenic Damage, Conservation Loss, Pest and Fungal Deterioration	Cultural Value (f1), Natural Value (f2), Spiritual Value (f3), Functional Value (f4), Historical Value (f5), Cultural Transmission (f6), Collective Memory (f7), Traditional Craftsmanship (f10), Development Planning (f11), Development Models (f12)
	human-led conservation	Conservation Boundary, Comprehensive Conservation	Cultural Transmission (f6), Collective Memory (f7), Development Planning (f11), Development Models (f12)

). The selection and confirmation of these 83 elements indicate their higher levels of social attention, sustainability relevance, and evaluative conditions across multiple data platforms, thereby highlighting their significant potential for in-depth research.

3.1.2. Classification of Protected Elements

Based on the inherent hierarchical relationship between explicit and implicit conservation elements, the 83 high-frequency terms were categorized into two major groups: explicit elements (67 terms) and implicit elements (16 terms) (Table 2).

(1)

Explicit elements

Explicit elements refer to the material and structural components of heritage conservation. These were further divided, according to their affiliation with the five overarching conservation categories, into 12 primary-level explicit elements and 55 secondary-level explicit elements. The secondary-level elements represent specific actions, features, or subcomponents related to their corresponding primary-level elements.

(2)

Implicit elements

Implicit elements, by contrast, represent the core values underpinning heritage conservation. A total of 16 implicit elements (denoted as f1–f16) were identified. These elements rely on explicit elements as their physical carriers and serve to guide, shape, and influence the external expression of heritage entities. As such, the preservation of implicit elements should be prioritized over that of explicit ones. Furthermore, implicit elements are not subject to alteration due to the loss of material forms, making them a crucial standard for assessing the long-term value of heritage. Importantly, a single implicit element can manifest through multiple explicit elements, while an individual explicit element may also be influenced by several implicit elements. For example, architectural composition and cultural development are both shaped by regional culture (f14), whereas both cultural value (f1) and regional culture (f14) contribute to the expression of architectural identity and cultural functions [40]. Therefore, the transmission and preservation of implicit elements must be addressed through targeted conservation strategies that correspond to their associated explicit elements.

3.2. Classification of Conservation Elements for the Great Wall Heritage

3.2.1. Establishment of Evaluation Criteria

To quantitatively assess the importance of the implicit elements (f1–f16) within the Great Wall heritage conservation lexicon, data derived from the China National Knowledge Infrastructure (CNKI) were used as the basis for evaluation. Specifically, the number of academic publications related to each implicit element was collected and analyzed as a quantitative measure of scholarly attention. The evaluation was conducted using five comprehensive indicators, categorized into three dimensions: (

Table 3. Raw acquisition data.

Evaluation	f1	f2	f3	f4	f5	f6	f7	f8	f9	f10	f11	f12	f13	f14	f15	f16
A1	140	26	69	425	98	370	76	126	61	15	141	318	117	191	128	10
A2	27.5	133	58	30.4	90	60	41.6	0	52	−42	6	0	158	−26	−39	−10
A3	5.4	1.9	3	13.7	4.7	15.4	4.2	4.5	2.9	1.3	4.9	12.2	7.9	9.1	5.1	1.4
A4	28	24	5.4	1.4	66.2	34.4	59.6	8.8	15	27.2	10.4	−5.2	34.8	12.6	2.2	43.2
A5	3	7.6	8.8	5.8	3.8	11.2	23.6	3.2	5.4	27.2	7.8	−1	42	7.4	0.2	−6.2

)

(1)

Academic Attention

A1: Total number of related academic publications;

A2: Compound annual growth rate of publications from 2019 to 2024;

A3: Average annual publication volume over the same period.

(2)

Media Attention

A4: Average annual growth rate of newspaper coverage from 2019 to 2024.

(3)

Academic Dissemination

A5: Average annual growth rate of citation frequency from 2019 to 2024.

These five metrics were employed to establish a comprehensive evaluation system for measuring the relative influence and research intensity of each implicit element, thereby providing a data-driven foundation for prioritizing elements in the context of living heritage conservation strategies.

By entering the corresponding latent factor keywords into the advanced search function of CNKI (China National Knowledge Infrastructure), one can retrieve the original data for relevant evaluation indicators. This dataset encompasses both Chinese and international academic publications indexed within CNKI. The final correlation results derived from this evaluation demonstrate a certain degree of stability. This is primarily due to the relative consistency of indicators such as month-on-month growth volume and growth rate, which are regulated by the latent factor. If the number of publications increases annually within a controlled proportional range, the fluctuation in correlation outcomes remains minimal. Therefore, under relatively stable environmental conditions, academic research data indicators are more representative of current research trends and focus compared to indicators such as community participation or economic metrics.

3.2.2. Evaluation Model Construction

Both qualitative and quantitative analyses were applied to assess the weight and priority level of implicit elements within the framework of living heritage conservation for the Great Wall. By utilizing the evaluation indicators associated with implicit elements, corresponding indicators for explicit elements were subsequently derived, allowing for a systematic assessment of their relative importance. This approach ensures that the value and influence of explicit elements are interpreted in the context of their underlying implicit dimensions. The construction of the evaluation model followed a structured methodology, comprising the following steps [38]:

(1)

Element Selection—Identification of relevant implicit and explicit heritage conservation elements.

(2)

Data Normalization—Standardization of raw data to eliminate dimensional differences and enable comparative analysis.

(3)

Construction of the Reference (Mother) Sequence—Establishment of a benchmark sequence representing ideal values.

(4)

Calculation of Grey Relational Coefficients—Measurement of the degree of association between individual elements and the reference sequence using grey system theory (

Table 4. Relational coefficient.

Evaluation	f1	f2	f3	f4	f5	f6	f7	f8	f9	f10	f11	f12	f13	f14	f15	f16
A1	0.31	0.03	0.14	1.00	0.21	0.87	0.16	0.28	0.12	0.01	0.31	0.74	0.26	0.44	0.28	0.00
A2	0.40	1.00	0.57	0.41	0.75	0.58	0.48	0.24	0.53	0.00	0.27	0.24	0.80	0.09	0.01	0.18
A3	0.30	0.04	0.12	0.88	0.24	1.00	0.20	0.23	0.11	0.00	0.26	0.77	0.47	0.55	0.27	0.00
A4	0.53	0.48	0.25	0.20	1.00	0.60	0.91	0.29	0.00	0.52	0.31	0.11	0.61	0.34	0.20	0.72
A5	0.20	0.29	0.31	0.25	0.20	0.36	0.61	0.06	0.01	0.70	0.29	0.10	1.00	0.28	0.13	0.00

).

(5)

Formation of Relational Sequence—Ranking of elements based on their grey relational degree to determine their relative importance (

Table 5. The correlation degree of implicit Conservation elements.

Evaluation	f1	f2	f3	f4	f5	f6	f7	f8	f9	f10	f11	f12	f13	f14	f15	f16
Relational	0.44	0.52	0.42	0.61	0.57	0.67	0.53	0.39	0.38	0.43	0.41	0.49	0.63	0.44	0.38	0.4

).

This process enabled a comprehensive and hierarchical evaluation of conservation elements, contributing to more targeted and evidence-based strategies for the sustainable and dynamic preservation of the Great Wall as a living heritage.

Based on the calculated results of the grey relational analysis, the degree of association between the 16 implicit elements and the conservation of the Great Wall heritage was ranked in descending order as follows: f6 Cultural Transmission (0.67), f13 Great Wall Culture (0.63), f4 Functional Value (0.61), f5 Historical Value (0.57), f7 Collective Memory (0.53), f2 Natural Value (0.52), f12 Development Models (0.49), f14 Regional Culture (0.44), f1 Cultural Value (0.44), f10 Traditional Craftsmanship (0.43), f3 Spiritual Value (0.42), f11 Development Planning (0.41), f16 Religious Belief (0.40), f8 Historical Environment (0.39), f9 Political Environment (0.38), and f15 Ethnic Culture (0.38).

This ranking reflects the relative importance of each implicit element in shaping conservation priorities. The results highlight the central role of cultural transmission, the intrinsic cultural identity of the Great Wall, and its functional and historical significance in guiding living heritage conservation strategies. These findings provide a robust basis for aligning explicit conservation efforts with the most influential underlying values.

3.2.3. Classification of Protection Elements

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Classification of Implicit Conservation Elements

Classification of Implicit Conservation Elements: Implicit elements with a grey relational degree ≥0.51 are categorized as Level I (core) conservation elements. Elements with a relational degree <0.51 and ≥0.41 are classified as Level II (important) conservation elements, while those with a degree <0.41 are designated as Level III (basic) conservation elements (

Table 6. Classification of implicit Conservation elements.

Level	Implicit Elements
Level I (core) conservation elements	Cultural Transmission, Great Wall Culture, Functional Value, Historical Value, Collective Memory, Natural Value
Level II (important) conservation elements	Development Models, Regional Culture, Cultural Value, Traditional Craftsmanship, Spiritual Value, Development Planning
Level III (basic) conservation elements	Religious Belief, Historical Environment, Political Environment, Ethnic Culture

).

Based on the ranking of grey relational degrees, the following conclusions can be drawn:

Cultural transmission received the highest correlation score, closely followed by Great Wall culture and functional value, all of which fall within the same top-tier classification. The minimal score differences among them indicate that these elements have consistently been regarded by scholars as primary considerations in heritage conservation.

While historical value, collective memory, and natural value are also classified as Level I conservation elements, their scores are relatively lower. This suggests that although they are gaining importance, they have only recently emerged as focal points in academic research.

The implicit elements ranked in the middle and lower tiers exhibit closely clustered scores, with some sharing identical values. This reflects a similar level of significance among them, implying that these elements can be addressed collectively in the formulation of conservation strategies for the Great Wall.

Ethnic culture received the lowest score among the implicit elements. This can be attributed to two primary factors. First, current research tends to prioritize other aspects of value, resulting in fewer explicit linkages between ethnic culture and Great Wall conservation. Second, much of the ethnic cultural knowledge remains embedded in the memories of original village inhabitants or within the broader framework of ideological superstructures. This makes it less accessible to scholars in the field of architecture and related disciplines, leading to lower levels of academic attention and correspondingly lower scores.

Overall, the core intangible value of the Great Wall that people believe should be preserved lies primarily in cultural inheritance. This dimension has become the foremost consideration in guiding conservation efforts. The aspects of history and collective memory contribute positively to the comprehensive planning and implementation of heritage conservation for the Great Wall. In contrast, deeply rooted elements such as ethnic culture—while significant—pose challenges to research due to their inherent complexity and limited operability within analytical frameworks.

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Classification of Explicit Conservation Elements

Given that the expression and manifestation of explicit elements are guided and influenced by implicit elements, the evaluation scores for explicit elements are derived from the weighted average of their associated implicit elements. Based on this, explicit elements with a score ≥ 0.50 are categorized as Level I (core) conservation elements; those with scores > 0.46 and < 0.50 are classified as Level II (important) conservation elements; and those with scores ≤ 0.46 are designated as Level III (basic) conservation elements (

Table 7. Classification of explicit Conservation elements.

Protection Level	Explicit Elements	Implicit Elements	Comprehensive Score
Level I (core) conservation elements	cultural development	Cultural Value (f1), Spiritual Value (f3), Functional Value (f4), Cultural Transmission (f6), Collective Memory (f7), Great Wall Culture (f13), Regional Culture (f14), Ethnic Culture (f15), Religious Belief (f16)	0.50
	architectural composition	Cultural Value (f1), Spiritual Value (f3), Functional Value (f4), Historical Value (f5), Cultural Transmission (f6), Collective Memory (f7), Historical Environment (f8), Traditional Craftsmanship (f10), Regional Culture (f14), Ethnic Culture (f15), Religious Belief (f16)	0.50
	damage and deterioration	Cultural Value (f1), Natural Value (f2), Spiritual Value (f3), Functional Value (f4), Historical Value (f5), Cultural Transmission (f6), Collective Memory (f7), Traditional Craftsmanship (f10), Development Planning (f11), Development Models (f12)	0.51
	human-led conservation	Cultural Transmission (f6), Collective Memory (f7), Development Planning (f11), Development Models (f12)	0.53
Level II (important) conservation elements	activation forms	Cultural Value (f1), Natural Value (f2), Spiritual Value (f3), Functional Value (f4), Cultural Transmission (f6), Collective Memory (f7), Political Environment (f9), Development Planning (f11), Development Models (f12), Great Wall Culture (f13), Regional Culture (f14), Ethnic Culture (f15), Religious Belief (f16)	0.46
	architectural characteristics	Cultural Value (f1), Natural Value (f2), Spiritual Value (f3), Functional Value (f4), Historical Value (f5), Cultural Transmission (f6), Collective Memory (f7), Historical Environment (f8), Development Planning (f11), Development Models (f12)	0.48
	public environment	Natural Value (f2), Functional Value (f4), Historical Environment (f8), Development Planning (f11), Regional Culture (f14)	0.47
	basic infrastructure	Cultural Value (f1), Spiritual Value (f3), Functional Value (f4), Historical Value (f5), Cultural Transmission (f6), Collective Memory (f7), Development Planning (f11), Regional Culture (f14), Ethnic Culture (f15), Religious Belief (f16)	0.49
Level III (basic) conservation elements	industrial types	Cultural Value (f1), Functional Value (f4), Historical Environment (f8), Political Environment (f9), Development Planning (f11), Development Models (f12), Regional Culture (f14)	0.45
	natural conditions	Natural Value (f2), Historical Value (f5), Historical Environment (f8), Political Environment (f9), Development Planning (f11)	0.45
	geographic location	Natural Value (f2), Historical Value (f5), Historical Environment (f8), Political Environment (f9), Development Planning (f11), Regional Culture (f14), Ethnic Culture (f15), Religious Belief (f16)	0.43
	architectural morphology	Functional Value (f4), Collective Memory (f7), Historical Environment (f8), Political Environment (f9), Regional Culture, (f14), Ethnic Culture (f15), Religious Belief (f16)	0.44

).

For the Level I explicit conservation elements, particularly those related to damage and deterioration as well as human-led conservation, restoration and protection efforts should be guided by the value orientation embedded within the implicit elements and aligned with established heritage conservation principles. Similarly, elements concerning cultural development and architectural composition should be developed and managed with a focus on the transmission and promotion of the cultural and historical significance of the Great Wall. For Level II explicit elements, including activation forms, architectural characteristics, public environment, and basic infrastructure, enhancement, construction, and restoration should be undertaken under the premise of safeguarding implicit value connotations and ensuring the long-term sustainability of the heritage. As for the Level III explicit elements, such as industrial types, natural conditions, geographic location, and architectural morphology, these should be systematically categorized and documented to enrich the historical archive, thereby providing a foundational reference for future restoration initiatives.

4. Discussion

Based on the six fundamental steps of “living heritage conservation” summarized by Prelos, the guidelines for the living transmission of “traditional villages” (which prioritize cultural inheritance, adopt development planning as a guiding principle, and focus on traditional craftsmanship and regional culture), as well as the case study of the living conservation design of the Shixia Great Wall Folk Residence Museum (which adheres to the principles of integrity and dynamism—extending from the physical continuity of the site to the expansion of its spiritual connotations and the interpretation of genius loci in exhibition design), this study proposes a functional repositioning of the Great Wall. It suggests reestablishing connections with core communities (e.g., local villagers and site staff), as illustrated (Figure 6), while also involving peripheral communities, which may include, but are not limited to, residential communities (nearby local residents), economic stakeholders (such as vendors), cultural transmission groups (including traditional craftsmen and artisans), out-migrated indigenous populations, and younger generations (whose connections to the heritage site are maintained through cultural memory and traditional narratives).

Based on this framework, a revised set of six core steps for the “living” conservation of the Great Wall is proposed [41]:

1. Constructing the Relationship Between the Great Wall Heritage and Local Villagers (Living and Production Relationships): The first step is to determine the applicability of the concept of living heritage. Following this, it is essential to identify core and peripheral communities. Once identified, the study should explore effective channels to establish connections between the heritage site and local villagers. These may include museums, national parks, heritage conservation bases, and cultural and creative industries, which can serve as sustainable sources of economic revenue.

2. Establishing Collaborative Mechanisms with Core Communities for Joint Conservation Efforts: Based on newly constructed relationships, cooperation with local villagers should be actively promoted to jointly protect the physical structure of the heritage site. This collaboration may include roles such as heritage patrols, tour guiding, and service-related partnerships. Such arrangements can provide indirect and implicit economic benefits to the communities involved.

3. Integrating Core Conservation Values with Modern Scientific Methods to Formulate Heritage Conservation Plans: This involves incorporating sustainable development principles into both conservation practices and community development. Specific strategies include designing long-term mechanisms for continued heritage conservation, establishing traditional time-based management systems, and maintaining practices centered on the core communities.

4. Assessing and Categorizing the Tangible and Intangible Values of the Heritage Under the Guidance of Core Communities: This approach advocates a shift from a material-centric conservation model to one that prioritizes the cultural significance and intrinsic values of the Great Wall heritage. It aims to move beyond traditional “static” preservation by emphasizing dynamic, evolving modes of inheritance and protection.

5. Developing Heritage Conservation Plans Centered on Core Community Members: The formulation and implementation of heritage protection initiatives must prioritize local core villagers, ensuring that conservation efforts are aligned with local economic and ecological needs. Protection strategies should be context-specific and rooted in the shared interests and distinct characteristics of the communities involved.

6. Conducting Periodic Evaluations and Revisions of the Great Wall Heritage Conservation Action Plan: This entails the development of both long-term and short-term objectives for heritage protection, with flexible management and response strategies adjusted according to the degree of goal attainment. The ultimate aim is to achieve a model of “living” heritage conservation.

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Implicit Elements:

For Level I conservation elements such as cultural transmission, Great Wall culture, and collective memory, which pertain to the intangible and spiritual dimensions of heritage, protection efforts should follow the fourth step of the revised Living Heritage Approach. This includes conducting ethnographic interviews with local villagers to collect and curate folklore associated with the Great Wall—such as tales of the Han dynasty’s campaigns against the Xiongnu, the Tang resistance against the Turks, the Song battles with the Khitan, and the Ming confrontations with the Oirat Mongols. These narratives should be evaluated and enriched to highlight the historical conflicts between nomadic northern peoples and Han Chinese civilization, thereby forming the thematic basis for the dissemination and preservation of the so-called “Guangwu Legends” [42]. For the conservation of historical and functional values, public education and knowledge dissemination campaigns should be prioritized [43]. The natural values should be preserved through the integration of local flora and ecological resources, with landscape design tailored to both environmental and aesthetic functions in accordance with the region’s geographical characteristics [44].

For Level II implicit elements such as development models and planning strategies, conservation should align with the first three steps of the revised framework. This includes establishing heritage-based economic infrastructures such as the Great Wall National Cultural Park, a site-specific heritage museum, and a scenic greenbelt. These efforts not only protect the physical remains of the Great Wall but also foster new forms of cooperation with local villagers, offering employment opportunities and promoting regional economic revitalization [45]. The conservation of traditional craftsmanship should be grounded in the transmission of knowledge among core community members and supplemented with modern preservation techniques for documentation and archival purposes. Protection of regional culture, cultural value, and spiritual significance—along with Level III elements such as religious beliefs, historical context, political environment, and ethnic traditions—should focus on the systematic collection of visual and historical records. These materials must be organized, categorized, and formally archived to compile a comprehensive documentation set of the Ming Guangwu Great Wall, thereby laying a foundation for future research and related scholarly endeavors [46].

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Explicit Elements:

For Level I explicit elements such as architectural composition, physical deterioration, and manual conservation efforts, protection measures should align with the fifth and sixth steps of the revised Living Heritage Approach. These actions should incorporate traditional craftsmanship, local environmental conditions, and indigenous materials. Repair and restoration work on the architectural structures should be collaboratively undertaken with local core community members. Furthermore, ongoing supervision and maintenance should also involve local participation to ensure sustainable stewardship [47]. In terms of cultural development, emphasis should be placed on the modern reinterpretation and expression of cultural values. This could involve the creation of culturally themed products and spaces, such as cultural and creative merchandise, thematic cafés, libraries, and exhibitions. By integrating new formats and contemporary visual identities, such initiatives can expand the cultural reach and visibility of the Great Wall [48].

For Level II explicit elements, the aspect of revitalization formats mirrors the implicit elements of development models and planning strategies. These may include the construction of “new architectural forms” that provide contemporary functions and thereby “revitalize” the heritage site. With regard to architectural characteristics, conservation should be informed by implicit elements such as traditional craftsmanship and regional cultural influences. Detailed documentation of architectural traits should be undertaken to guide future restoration efforts. For public and foundational environmental elements, infrastructure development and environmental protection should be prioritized [49]. Zoning and spatial strategies should aim to create cohesive landscape clusters. Additionally, collaborative development with nearby major cultural and historical sites—including Yanmenguan Pass, the Old Guangwu City, the Guangwu Han Tomb Group, and Mount Wutai—should be pursued to establish a regional cultural tourism network and promote integrated development.

For Level III explicit elements, industrial transformation should be based on building new cooperative relationships with local core community members, encouraging a shift from traditional agriculture to a cultural economy. As for the natural conditions, geographic location, and architectural morphology, which are foundational attributes dating back to the original construction phase of the Great Wall, systematic analysis and documentation are required to support future conservation and interpretation efforts [50].

From a comprehensive perspective, the “living transmission” of the Ming Guangwu Great Wall should be advanced through the following strategies:

1. Assessment and Restoration Grounded in Local Context: The evaluation and restoration of the heritage site should be based on key local elements, including the resident population, environmental conditions, and the use of locally sourced materials. Assessment efforts should primarily focus on identifying damaged areas and zones affected by development. Restoration strategies should also account for the impact of vegetation, considering both its destructive potential and its use as a protective soft covering layer.

2. Establishing New Collaborative Frameworks through Heritage Infrastructure Development: Building upon physical restoration, new cooperative relationships should be established through the development of heritage infrastructure such as the Great Wall National Cultural Park, a Great Wall Site Museum, and landscape greenbelts. These efforts aim to enhance basic services, improve the surrounding environment, and upgrade associated facilities.

3. Preservation and Planning for Intangible Cultural Heritage: Particular attention should be given to the preservation and documentation of intangible cultural elements. Future development plans should include objectives such as shaping the overall scenic identity of the site, integrating the heritage site with surrounding regions, and incorporating wellness and cultural tourism infrastructure. These efforts will support the sustainable and dynamic continuation of the heritage in alignment with local needs and characteristics.

As this study on the components of Great Wall conservation based on the “living heritage conservation approach” uses the Ming Great Wall in Shanxi Province as its case study, further comparative research should incorporate region-specific characteristics and apply weighted coefficients accordingly. Given that different scholars emphasize varying aspects of Great Wall heritage, the relative importance of implicit elements may differ across heritage sites. Therefore, the classification and grading system of conservation elements proposed in this paper should be viewed as an initial framework. The prioritization of conservation tasks at various Great Wall sites may deviate depending on the weight assigned to specific elements, necessitating adjustments based on the specific conditions of each site. This requirement for adaptability aligns with the core principle of the “living heritage conservation approach,” which emphasizes flexibility. Ultimately, the structure of the conservation element system should integrate the subjective judgment of the core community, thereby ensuring context-sensitive, targeted conservation strategies.

5. Conclusions

This study, grounded in the concepts of “Living Heritage Conservation” and the “Cultural Iceberg” model, employed a combination of questionnaire surveys, grey relational analysis, and qualitative regional zoning to classify, evaluate, and analyze the conservation elements of the Ming Guangwu Great Wall. The key findings are as follows:

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The current physical structures of the Ming Guangwu Great Wall, including wall segments, watchtowers, and beacon towers, are well preserved. The site demonstrates high accessibility, is surrounded by rich natural and cultural landscape resources, and has strong potential for visual and tourism appeal. However, the area currently lacks systematic conservation and management strategies.

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A total of 83 conservation elements related to the Ming Guangwu Great Wall were identified, consisting of 67 explicit elements and 16 implicit elements. A comprehensive conservation element database was constructed. Analysis revealed that implicit elements hold higher conservation priority than explicit elements, as implicit values are expressed through explicit forms and, in turn, influence the manifestation of explicit elements.

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Based on the analysis of data related to the 16 identified implicit elements, the current research hotspots were identified. An evaluation model was subsequently developed to classify these elements, resulting in a zoning of both explicit and implicit elements. This allowed for the determination of differentiated levels of protection required for each zone. Furthermore, a newly proposed six-step strategy for the “revitalization” of the Great Wall was introduced. Accordingly, a series of practical conservation measures were developed for both the explicit and implicit elements of the Ming Guangwu Great Wall. For the implicit elements, the focus lies in the establishment of new development models and the formulation of development plans, emphasizing the transmission of intangible cultural and spiritual values. Special attention is given to the systematic collection and documentation of related elements. For the explicit elements, conservation and restoration methods are proposed based on local contextual conditions. These include strategies for long-term maintenance, improvements in infrastructure, environmental optimization, promotion of economic transformation, and historical background documentation.

The conservation of the Great Wall heritage involves complex elements and spans a vast spatial scale. This study focuses on identifying and implementing conservation measures based on data-driven analyses of key heritage elements. Future research may benefit from integrating additional methodologies and conducting more in-depth investigations into the composition of conservation elements and the technical practices of restoration.