Towards Monuments’ Holistic Digital Documentation: the Saint Neophytos Enkleistriotis Case Study

Abstract

The expansion of the term “monument” to include the surrounding area of the tangible cultural asset, its natural environment as well as the intangible data relating to its existence and use has gradually resulted the formation of the term “cultural landscapes”. “Monument” has evolved into “monumental place” and a “place with its own soul” and nowadays into a “unity” incorporating the multiple and diversified views which regard the one and single object, the cultural asset. In this paper and through the presented case study of Saint Neophytos Enkleistriotis monument, we attempt to move further on, from the view of the “unity” and the interdiscipilinary approach to the “holistic” view, treating the cultural asset as a “whole”; a “whole” which will have been created from the harmonious merge of all the multifaced entities of which it is comprised.

1 Introduction

The emergence of a holistic approach to monument documentation is inextricably associated with the term ‘monument’, the quest of its meaning and its interpretation to the people involved in the documentation of the past. The term ‘monument’ has been transmitted many times following the evolutionary expansion of the concept of ‘heritage’ and its semantical transfer into ‘Cultural Heritage’ (CH). The main reason was the necessity to set tangible heritage in its wider context, and relate it with its physical environment and its intangible aspects (spiritual, political and social values) [1–3]. Both the existing natural and cultural diversity among the nations of the world and the appreciation of intangible heritage -as the primer fundamental element before its materialization into tangible heritage- led to a more anthropological, holistic heritage approach. Moreover, the infiltration of culture and nature in the concept of ‘cultural landscape’ as well as the broadened shift towards viewing historic buildings as an inseparable part of historic cities and sites, revealed the matter of ‘monumental place’. In this way, a monument can be seen as a whole, within a place with a soul – a genius loci [4].

Monumental places are places of cultural identity and of great human achievement. While the tangible part of a monument may leave its material evidence in the course of time, the intangible part, which is more closely related to its creator, may never survive. The survival of intangible heritage is then depended on the onward (mainly oral) transmission of the knowledge behind its creation and the values it reflects: historical values, symbolical values, authenticity and quality. It is a transmission of practices, knowledge and skills that encapsulate a form of ‘memory’ of the built heritage and its relationship between the society and a normative system of ideas and beliefs. Consequently, ‘values’ and ‘memory’ are the substances that transform a built structure into a monument and are only a part of what the holistic documentation approach aims to capture. Due to the variety of its individual components (both tangible and intangible, material and immaterial, concrete and abstract, natural or artificial), monument documentation demands the coincidence of the effort of many scientific, engineering, and management disciplines to become a reality in order to gather all these kinds of professional data. Hence, interdisciplinary research and cross-sectorial approaches among the CH domain, that integrate knowledge and methods using real synthesis, can lead to the augmentation of documentation tools and standards in establishing holistic practices. Data collection for monumental buildings, complexes, settlements, areas, artifacts during documentation deals with “visible” data. This includes the documentation of past indications about monument’s remains through geospatial surveying of its form, the recording of the materials used for its first creation and possible later interventions as well as the construction technology, which can lead to adequate pathology analysis and effective conservation of the building [5]. Along with the visible data, the “invisible” data, such as occurred past events, stories of the lives of the users and the local community, songs and lyrics written about it, liturgies in the case of religious monuments etc., will constitute the finishing layers that would deliver a unified information and knowledge hub.

Extending narrow and sterile considerations, the approach does not seek to “freeze” the intangible part of the monument, by reducing it into files, be in archives, inventories, museums, libraries, text, audio and video records [2]. Besides, it aims to creatively “revive” it by further exploiting every technological affordance of the present era. Eventually, holistic approach for monuments’ digital documentation is oriented to provide the framework -a basis- for the ongoing adjustment and evolvement of the effective, multileveled and multi-perspective reuse of the documented information by the diverse user groups involved in the creation, use and dissemination of digital cultural heritage.

This paper focuses on holistic approach documentation activities partaken at St. Neophytos church; a church with tremendous monumental interest both of its tangible and intangible aspects as well as the unique blending of natural and man-made environment that bears the signs of human work and the effect of multicriterial factors that have shaped so far the history of the religious monument.

2 Methodology

The Digital Documentation of Monuments has met vast progress in recent years, since it develops parallel to the Information, Communication and Technology (ICT) sector. However, because of this fast development, digital documentation has also left many gaps and created challenges on data quality, accuracy, standards, archiving, copyrights and sustainability. There is a need to establish a methodology and a workflow, where various users (experts and non-experts) should follow, aiming to maximize collaboration, distribution and -at the end- capitalize the digital information of the monument. The proposed methodology of holistic approach presents a workflow that could (at the full end level) answer the requirements of the monuments’ digital documentation, filling the above mentioned gaps, by involving all user needs from the beginning of the process. Counting users’ needs on planning and implementing the holistic digital documentation is crucial due to the fact that the documentation sector as well as the whole life cycle of a digital cultural heritage asset, are by nature multidisciplinary (and during the documentation process become interdisciplinary). Therefore, before deciding “what kind of data do I need (from them)” it is essential to have an integrated image of the potential users’ needs; their interrelationships, their intersectorial agendas (in which phase of the documentation process do they meet), the problems they are coming up against during the process and how they overcome those. This feedback, together with the required types of data, will enrich the metadata (data about data) and organize the semantics (information that needs to be interlinked) in order to shape system’s ontology (monument’s conceptual model), countering the above mentioned challenges (data quality, accuracy, standards, intellectual properties and sustainability).

The first step towards the proposed methodology of holistic digital documentation is the analysis of cultural heritage users and stakeholders. They can be categorized in two major teams: experts and non-experts [6] (Table 1); “experts” are users that create digital data from documenting monuments and “non-experts” are users that only use these data. Nevertheless, due to the fast development of the creative sector -especially in EU- the “non-experts” are creating new content that we cannot afford to leave outside the monuments’ digital documentation, especially in the holistic approach. Hence, the boundaries of these teams are loose, leaving many non-experts to become experts due to their engagement, knowledge and creativity on specific cultural heritage assets (Fig. 1). On our proposed approach, expanding the boundaries between these teams is our aim; including more non-expert users in planning and digital documenting monuments augments the results, increases the coverage of the intangible heritage aspect, minimizes the possibility of faults and maximizes the prospects of reusing the digital data.

Table 1. Users’ teams (expert and non-experts)

Fig. 1.

Experts and non-experts users’ engagement in holistic digital documentation

The second step is a parallel analysis of the cultural heritage information that we need to extract from the monuments’ digital documentation. According to Core Data Index for historic buildings and monuments of the architectural heritage and its basic aim, a possible classification of individual buildings and sites is by: name, location, functional type, date, architect, building materials and techniques, physical condition, and protection status [7]. In addition, it should be taken under consideration the fact that depending on the country or the organization, the need for deeper levels of architectural, archaeological, environmental, historical, and planning information will vary; each one must define its own specific requirements. Towards the digital holistic approach, the data (and metadata) that we need to document should expand and adjust to the quality restrictions given by ICT experts. A holistic unity of intellectual frameworks and approaches of information gathering beyond the disciplinary perspectives, is crucial for the sufficient implementation of an effective, transdisciplinary and collaborative work methodology that aims to define data collection process, case study setup, selection and utilization of systems and instruments, knowledge management, implementation of semantically enriched models, exploitation in education and business and the continuous advancement of the information gathered and reused. In Fig. 2, the proposed data and metadata scheme clearly presents the necessity for a horizontal connection of Digital Documentation with all data (and metadata) categories [5]. As digitalization is a procedure that could be applied in analogue data, it is necessary to clarify that the proposed holistic methodology requires the plethora of the documentation to be digital and not digitized. That said, obviously we can’t avoid analogue data, especially during historic research, so digitalization will be applied following the same scheme of metadata. Last but not least, the 3D documentation of the monument is essential for holistic approach; documenting and creating the 3D model is a procedure that involves a number of users (experts and non-experts) that can directly benefit from the information covered by the 3D and many of them could (and should) offer data to upgrade the quality and enrich the information of the 3D model.

Fig. 2.

Basic data and parameters documentation for holistic digital approach

In the case study of Saint Neophytos, the proposed methodology workflow was followed. At the beginning there was an effort to cover a number of users (experts and non-experts) in the process of documentation (Fig. 1). Since the approach is digital, various methods were discussed and the team developed a scheme of data collection aiming towards the holistic digital documentation methodology. In the first phase of the documentation the developing of the 3D Model was the crucial part of the workflow. In Fig. 3 one can see the representation of how different users are involved to collect the data from the monument to develop the 3D Model; at the same time, users absorb the extracted information to create new content; this way many of them are upgraded from non-expert users to expert users. An example of the high value of the 3D digital model in our case study is the demand that the documented information should be vastly useful for structural analysis (by Archaeologists, Historians, Architects & Civil Engineers), for pathology and conservation state analysis (Civil Engineers, Conservators and Architects), for hazard analysis (Geologists, Civil Engineers, Architects, Policy Makers), for humanities analysis (Historians, Architects, Curators, Multimedia developers) for intervention analysis (Architects, Civil Engineers, Historians, Archaeologists, Electrical & Mechanical Engineers, Curators) and finally for monuments value analysis (Historians, Architects, Archaeologists, Civil Engineers, Policy Makers, Curators, Stake Holders, Conservators).

Fig. 3.

Different Users’ involvement in holistic digital documentation of the monument of Saint Neophytos.

The outcome of the digital documentation of the Enkleistra of Saint Neophytos is a highly-detailed 3D model, which may act as a reference point for the creation of applications in the field of Information Technology (IT). The specific 3D model provides incentives to developers in creating applications that will exploit model’s full potentials in order to become useful tools to either experts or non-experts. However, the proper function of these applications relies on the existence of a corresponding database on a server and/or on cloud systems, where the acquired data needs to be stored in a format that will be accessible and easily interpreted by all. Towards the scope of proper interpretation, it is essential to establish standards for the collected data, leading this way to a qualitative data collection with improved integrity and decreased number of stored redundant data. Taking into consideration database’s management, the stored data should follow the “Open Access” principles in order for its wider access and reuse to be ensured as different disciplines may enrich the database or even fulfill missing data. Parallel to that, a user friendly interface should be developed to help non-expert users to find the required information. The case study presented in this paper, is the first approach to Digital Holistic Documentation of Monument, using the proposed workflow. Obviously the project is ongoing and we are expecting interesting results, evaluation and limitations after the full deployment of user’s engagement.

3 The Saint Neophytos Enkleistriotis Case Study

3.1 Values’ Documentation

The Enkleistra of Saint Neophytos is an outstanding testimony of the Byzantine art and civilization at probably the most troubled and intense moments in this part of the Mediterranean: crusaders (English, Normans), byzantine and Arab elements are clearly reflected in the Enkleistra. The paintings (frescos) are characteristic of the “Komnenian” Byzantine art period (mid 12 century); one can identify strong emotions, mainly of passion and suffering, sophisticated proportions and movements of the figures who are dressed in rich clothes with wavy edges. There aren’t many frescos saved in such good conservation state as the ones in the monument of Saint Neophytos Enkleistriotis. The preservation of the Enkleistra and the extensive documentation of its origin, development and further interventions provide clear information for its interpretation and confirm the authenticity of each element. This existing written documentation, the structure, organization and paintings of the Enkleistra are key to understanding the ways of the monastic life in the twelfth century.

The organic form of the Enkleistra and the plasticity of the cave carved in the rock differentiates it from any other religious building around the island. It is situated in a unique landscape, excavated in a cliff overlooking a valley and has withstood landslides and earthquakes for more than 800 years. It has additionally been continuously used for monastic life and as a pilgrimage destination for centuries. These factors add to its historic and cultural value and attract people from all the corners of the globe until this day. Function, symbolism, use and the natural shape of the mountain are interconnected in this monument, unified and understood into a unique example of Cypriot religious architecture.

The history, the uniqueness of the structural form and the amazing frescoes, make the Enkleistra of Saint Neophytos a monument of an exceptional tangible and intangible cultural Cypriot -and world- heritage.

3.2 Geographical Documentation

The Enkleistra is situated in the southwest part of the island of Cyprus, north of Paphos, 6 km away from the sea, at an altitude of 450 m. above sea level; a strategic position which offered control over the coast (Fig. 4). The monastery complex is located in a natural valley oriented south. There is a small waterfall on the northern side of the cliff that continues into a stream running south. The Enkleistra is situated on its west part. The mountain cliffs are of a white calcareous rock, a workable material which is easy to be eroded by natural phenomena (rain, vegetation, landslides) and/or hewed by man, thus facilitating the creation (natural or artificial) of caves.

Fig. 4.

Geolocation of the Saint Neophytos’ Enkleistriotis monastery complex in Cyprus, north of Paphos (left); the New Monastery (centre); the Old Monastery (right)

3.3 Historical Documentation

Saint Neophytos Enkleistros (“The Recluse”) (1134 A.D.–1219 A.D.), was born in the town of Lefkara, near Larnaca. His life runs parallel in time with one of the most unstable political periods in Cyprus [8]. At the age of 17 years old he chose the monastic life and for five years remained at the St. Chrysostom monastery near Kyrenia, cultivating the land and learning how to read and write. After two years he set off for Jerusalem and shortly afterwards attempted to go to Asia Minor in search of solitary life and enlightment. His attempt was unsuccessful and therefore decided to become an ascetic at the hilly area above Paphos [8, 9]. In 1159 A.D. he departed for his place of reclusion and formed his cell by modifying an already existing one, encurved on the body of the mountain.

In this section there will also be incorporated various information regarding the stakeholders, testimonies, bibliography, possible past uses as well as legal status.

3.4 Architectural Documentation

Ever since 1159 A.D. Saint Neofytos spend the rest of his life in Enkleistra, thus he had furtherly modified the place, gradually turning Enkleistra from a single cave into a complex of caves and constructions (Figs. 5 and 6). Between 1159 and 1160 [8] Saint Neophytos dug two caves: his Cell, in which he used to live until 1197 A.D. and where his grave also lies, and a consecutive-to-the-cell cave with an altar (Bema), which was dedicated to the Holy Cross. Both of these caves constitute the “First Enkleistra”.

Fig. 5.

(sketch: adapted by Barskij)

Sketch of the Saint Neophytos’ Enkleistriotis monastery complex in 1735 A.D.; the New Monastery (centre); the Old Monastery (left)

Fig. 6.

(plan: adapted by [8])

Plan of various caves in the greater area of the old monastery complex - Level 1 (center), Level 3 (left)

In 1170 A.D., due to his growing popularity, Saint Neophytos was obliged to accept a disciple, establish a monastery and adjust the mountain structure/rock constructions to monastic rules. Consequently, the First Enkleistra got extended. This extension included the excavation of a third cave towards northeast (Naos) around 1183 A.D. [8] and the construction of an extra space on the eastern side (Exonarthex), in order for the functional causes of the orthodox church to be fulfilled. Probably for functional reasons of the monastery the cave of the Refectory (dining room) was also excavated on the north side of the three-cave unity.

Due to the increasing number of pilgrims Saint Neophytos dug another cave at a higher level (the New Zion or Higher Enkleistra), which was completed by the end of 1197 A.D. and in which he moved and spent the rest of his life until his death around 1220 A.D. in search of solitude. Gradually more spaces have been added, thus expanding the complex of the old troglodyte monastery. A closed room with a dome was constructed above the Exonarthex, the Sacristy, another closed room at a higher level of the Sacristy, the Holy Attendance and Sanctuary or Hagiasterion which is connected to the Naos through a narrow hole on the floor, as well as one more cave on the northern part of the cliff, above the Refectory (probably formed in 1170 A.D.), the Hermitage or Saint John Baptist Cave, which is devoted to the Holy Cross.

The old troglodyte monastery is composed of five different levels (Fig. 7): Level 0 (level of the bridge passing over the west stream), Level 1 (approximately 5 m above Level 0) where the Narthex, Naos, Bema, the Cell of the Saint and the Refectory are situated, Level 2 (Sacristy), Level 3 (Hagiasterion), Level 4 (the New Zion cell and the Saint John Baptist Cave). Because on the northeast (NE) side of the cliff there is a waterfall and a stream, the old monastery has expanded in the late twelfth century towards the southwest (SW), and as shown in the sketch made by Barskij (Fig. 5), some constructions already existed in 1735 A.D., possibly destroyed by a subsequent landslide. However, further to the SW, vestiges of other caves are traced, as well as stone building constructions used until not long ago by shepherds.

Fig. 7.

(photo: David Castrillo, 2016)

Facade of the old monastery complex with all five levels

In this section there will also be incorporated various information regarding the general typology, compared with other caves on a local and international level, possible evolution of typology, detailed architectural drawings on various scales based on the photogrammetric documentation.

3.5 Intervention Documentation

During the years 1963–1965 interventions of consolidation of the structure were carried out with the supervision of the Department of Antiquities of Cyprus. A covered veranda and five arches resembling the originals cited by the Saint were constructed (Level 1). Also stairs and paths from the Hagiasterion (Level 3) to the upper level (Level 4) were constructed.

In this section more detailed intervention data will be gradually added, in addition to a reference regarding intervention’s materials and interventions’ general assessment (actually solved problems or created new ones, successful or not successful, etc.).

3.6 3D Model Documentation

An important stage is the detailed documentation through the 3D recording of the monument; the products of this stage will be also used as the basemap for the studies of other specialists. First, the complete 3D geometric documentation of the Enkleistra via photogrammetric and surveying techniques is a fundamental step for addressing its structural and environmental problems. The results of the geometric documentation (sections, ortho-images, 3D models) will be provided to for its preservation and protection, as well as the planning of conservative repair operations. Furthermore, the generation of 3D printings or photorealistic 3D tours depicting in detail the internal and external parts of the Enkleistra is another objective of the 3D recording procedure and promotion of the monument.

3.6.1 Field Survey – Data Acquisition

As far as the geometric documentation of the Enkleistra is concerned, a combination of field surveying, terrestrial laser scanning, photogrammetric and computer vision techniques was applied. First, a geodetic network was established connecting the area in front of the rock, which includes the Enkleistra and the interior of all the rooms that exist inside the rock; so, all measurements and data collected can have a common georeference.

Scanning by a terrestrial time-of-flight laser scanner and image taking through terrestrial photography and the use of a small quadcopter UAV have been made at the external and surrounding area of the monument. A Canon EOS-1Ds Mark III camera was used for the acquisition of the terrestrial images (5616 × 3744 each) using two lenses of 24 mm and 16 mm focal length. Using the UAV, videos sequences depicting the external façade of the rock were taken by a GoPro camera, from a distance of 5 to 10 m from the object.

At the 4 rooms of the lower part of the Enkleistra, i.e., the old Enkleistra, which consists of the Naos dedicated to the Holy Cross (2 connected rooms) and the Cell of Saint Neophytos with his tomb, as well as the fourth separated room next to the Saint’s cell, and at the outdoor corridor from which doors lead into the lower part of the Enkleistra, multiple laser scans and the acquisition of more than 1,500 terrestrial images took place. The combined use of images, for the application of image-based 3D modelling techniques, and laser scanning was necessary for the complete coverage of the complex areas inside these rooms (e.g., inside the tomb of the Saint, under and around the Altar in the Bema and the table in the cell, inside recesses in the walls of the Enkleistra, etc.) In the rooms of the upper part of the Enkleistra (Level 4) only the acquisition of photos (a few dozens for each room) was sufficient for the creation of 3D models.

More than 200 ground control points (GCPs), including both artificial targets and natural features easily recognizable in the imagery, were measured using Total Station equipment for the georeferencing of the images; also, the retroreflective targets of the laser scanner were measured to co-register the image-based and laser-based point clouds.

3.6.2 Data Processing

The automatic creation of 3D models using image sequences relies on photogrammetric and computer vision algorithms. The first step of the image-based modelling pipeline is the Structure from Motion (SfM) process [10], which refers to the method of simultaneous computation of the camera six degrees-of-freedom poses (i.e., the camera exterior orientation of the images) and the sparse 3D geometry of the scene. Feature extraction algorithms, like SIFT [11] or SURF [12], image matching and robust outlier rejection techniques [13] are used, usually in combination with a sequential (incremental) algorithm [12, 13] for metric reconstruction, in case of calibrated cameras, or projective reconstruction, in case of unknown interior orientation; in case of uncalibrated cameras an auto-calibration process is implemented [14–16]. The georeferencing of the SfM outputs is generally performed by estimating the 3D similarity transformation between the arbitrary SfM coordinate system and the coordinate reference system using GCPs [17]. The process of dense image matching [18] is applied for the creation of a dense 3D point cloud using the camera exterior and interior orientation of the imagery, estimated by the SfM process. Then, a 3D mesh model can be created using the generated dense point cloud [19] via a surface reconstruction algorithm. Finally, texture mapping may be applied to the mesh model using the oriented images. The result of the image-based 3D modelling process is a photorealistic textured 3D surface model of the scene depicted in the imagery that refers to the coordinate system defined by the GCPs or the arbitrary SfM coordinate system, in case of lack of such kind of information.

The Agisoft PhotoScan software was used for the creation of dense point clouds using images taken by the Canon EOS-1Ds Mark III camera as well as frames of the videos taken by the GoPro camera. The processing of each internal room of the Enkleistra was performed separately. Similarly, the outdoor corridor and the external facade of the Enkleistra were divided into separate projects. The alignment of the images was the first step performed by PhotoScan; it is a SfM process that generates a sparse point cloud of the scene and computes the camera interior and exterior orientation, using a modification of the SIFT algorithm for the extraction of feature points. GCPs were manually measured in the corresponding images to transform the camera poses and the sparse point clouds into the local coordinate reference system. Furthermore, some regions of a few images (e.g., retroreflective targets, obstacles due to measuring equipment) were masked in the images, in order to reduce the subsequent editing of the resulting dense point clouds. Dense image matching was the next step applied through PhotoScan; the software calculates depth information for each camera and combines it into a single dense point cloud.

Due to the complexity of the Enkleistra, some small areas without cloud points were observed in the generated 3D dense point clouds (i.e., under the Altar, inside recesses, etc.). 3D information for such areas was derived by the point clouds generated by the laser scanner. The processing of the scans was performed via the Leica Cyclone software, including their registration via the common targets as well as their georeferencing, using the measured coordinates of the targets. The Geomagic Studio was used for the registration and merging of the laser-based and image-based point clouds, separately for each room of the Enkleistra, as well as their editing, including the removal of wrong and noisy cloud points. Furthermore, this software was used for surface reconstruction for each separate point cloud, resulting in 3D mesh surfaces for each room of the Enkleistra. In areas where the image-based point cloud was sufficient (i.e., upper part of the Enkleistra, corridor and exterior regions), only the editing of the point cloud and the meshing were performed via Geomagic software.

The reconstructed surfaces were inserted again into the PhotoScan environment for texture mapping, using the oriented images. The outputs of these steps are 3D textured models for every internal and external part of the Enkleistra. Finally, the textured mesh surfaces were merged via the Geomagic software. Except for 3D products, orthoimages at a resolution of 1 mm were generated via PhotoScan software, using the oriented images and the derived point clouds, by manually determining the level of section for each orthoimage. The orthoimages as well as the texture atlases of the 3D models were processed via the Adobe Photoshop software.

3.6.3 The 3D Model

The main product of the geometric documentation of the Enkleistra monument is a detailed and accurate 3D model which includes both the external areas (the rock and the newer constructions, like the corridor, etc.) and the internals of the rooms (of the upper and the lower part of the Enkleistra) georeferenced in a unique coordinate system, so that their relative horizontal and vertical position will be correct. In the following figures typical 3D views, ortho-images and horizontal and vertical sections of the monument are illustrated (Figs. 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 and 25).

Fig. 8.

Left: Projection on a single horizontal plane of the rooms of the Enkleistra that are at different levels (Level 1 up to Level 4) and the footprints of the vertical sections (AA and BB); Right: A view towards the ceiling at a horizontal section of the lower part of the Enkleistra

Fig. 9.

The vertical section A–A′′′ through the rock that includes the Enkleistra, with a metric scale of the relative elevations at the left (±0.00 m. at the entrance of Naos)

Fig. 10.

Left: The vertical section BB′; Right: The façade of the rock that includes the Enkleistra

Fig. 11.

3D view from the outside of the inside surfaces of the four rooms of the lower part of the Enkleistra (Level 1), as extracted from the point clouds of the laser scans.

Fig. 12.

3D of the view from the outside of the inside of the Naos dedicated to the Holy Cross

Fig. 13.

3D view from the inside of the 3D textured model of the Naos

Fig. 14.

Orthoimage of the western wall of the Naos

Fig. 15.

3D views from the outside of the inside of the Bema

Fig. 16.

Orthoimages of Bema Left: the northwestern wall - Right: the eastern wall

Fig. 17.

3D view from the outside of the inside of the Cell of Saint Neophytos with his grave

Fig. 18.

Othoimages of the Cell of Saint Neophytos; Top: the eastern wall - Bottom: the western wall

Fig. 19.

3D view of the textured model of the grave of Saint Neophytos

Fig. 20.

3D view from the outside of the inside of the Refectory

Fig. 21.

Orthoimage of the inside of the Refectory of the Enkleistra

Fig. 22.

3D views of the interior of the Sacristy; Left: Eastern wall - Right: Northern wall

Fig. 23.

3D views of the interior of the Hagiasterion of St. Neophytos; Left: Southern wall - Right: Western wall

Fig. 24.

3D views of the interior of the New Zion; Left: Southern wall - Right: Western wall

Fig. 25.

3D views of the interior of the Hermitage or Saint John Baptist Cave; Left: southern wall - Right: western wall future work

3.7 Structural Analysis

From a structural point of view, three different construction elements can be detected: the mountain rock, the stone masonry and the concrete. The mountain rock serves as back wall (western side) as well as ceiling of the caves, the stone masonry includes the walls, constructed to close the eastern façades of the excavated caves and which include openings for access or ventilation (doors and windows), while out of concrete are constructed all the contemporary interventions, namely the veranda (roof, arches, beams, columns) and possibly, the vertical reinforcement walls of the façade.

Regarding the structural condition, the latter additions in the period 1963–1965 (concrete beams, stone retaining walls) seem not to have helped to the stability of the monument. On the contrary, it can be an added problem, since a theory for the deteriorated state of the monument is that below exist hollow areas (probably previous rooms or auxiliary spaces like stables, etc. described by the saint in his writings). These voids, with the help of water infiltrated, seismic movements and the extra weight of the new interventions, could imply the displacement of the masonry stone walls and the evident detachment of the Narthex and the wall between them and also from the rest of the structure (Fig. 3). Moreover, the use of mortars rich in cement adds to the deterioration of the building structure.

In this section, the investigation of structure (description of bearing structure, construction techniques, distribution of building materials etc.) as well as mapping of structural state (e.g. mapping of structural cracks, disposition of elements, etc.) will gradually be included.

3.8 Building Materials’ Characterization

This section will include information about the type of materials (e.g. stone, mortar, ceramic, metal, etc.), their physical properties, their composition (e.g. chemical, petrographic, mineralogical), their mechanical properties as well as their processing (e.g. cost and availability, production, etc.).

3.9 External Hazards

The Enkleistra, being an integral part of the natural environment of the area, presents a variety of problems mainly caused by landslides and the characteristics, properties and morphology of the area, weather conditions, lack of adequate maintenance or intensive human contact. Landslides could potentially change the morphology of the mountain side and the quality of the rock allows it to break down easily, a phenomenon which is accelerated by earthquakes, rain, fauna and flora creating an additional safety concern for visitors. Earthquakes of high intensity, from 5 to 7° on the Richter scale, are frequent in the Paphos area. One must also note that fire is a great potential threat of the monument due to its location. The shape of the valley where it is placed creates a ‘no exit’ situation in the event of a fire originating from the lower part of the valley. Winds from the south would aid in the acceleration of the dimensions of such a fire.

The large attraction of visitors results in the change of the interior atmospheric conditions due to accumulation of people inside the monument as well as physical contact and photographing of the frescoes. Additionally, interventions due to contemporary needs (electricity etc.) and maintenance are often damaging or irreversible due to use of inappropriate and incompatible materials and new elements (electrical installation, lighting etc.).

In this section the environmental factors, the accidental actions, the impact of particular human actions as well as the social and economic parameters will be further on analyzed.

3.10 Conservation State – Pathology Analysis

The level of humidity in the cell is also quite high, thus numerous frescoes in the lower parts of the walls have undergone extensive degradation. The main pathologies caused by the aforementioned problems are missing or detaching frescoe parts evident in the lower levels of the walls (frescoes degradation, large lacunas, lack of adherence and hollow areas under frescoes) as well as growing cracks.

Cracks are mostly evident on masonry reinforced by new walls or concrete columns (Fig. 26). The most recent earthquake in 2015 created displacements inside the cave and further expanded the already existing cracks (Fig. 26). Given that the back wall (mountain rock) does not show major damage and through the analysis of the cracks, the theory developed is that these cracks were created due to cavities below the existing cave. A more in-depth study reveals that the whole narthex is detached from the masonry walls, and that the masonry walls are detached from the rock mountain. This creates three separate structural elements which have different structural behavior. More extensive research will reveal whether more caves (which seem to fail structurally) exist below Level 0, causing this type of extensive cracking (Fig. 27).

Fig. 26.

(architectural plan, David Castrillo 2016)

Construction materials and structural conditions

Fig. 27.

(photos and graphic recreation of frescoes: David Castrillo 2016).

Frescoes, conservation state with cracks and damaged areas

The diagnosis of decay which is derived from the usage of visual observations, non-destructive techniques, analytical testing, GIS decay mapping etc., the study of the mechanism of decay and the diagnosis of vulnerability (e.g. static and dynamic assessment, etc.) will be added to the provided aforementioned information.

3.11 Arts’ and Humanities’ Documentation

The architecture of the old monastery is inherently engaged with the layout of the frescoes and the presented iconographical themes. The digitally documented tangible structure is able to provide also a vast amount of intangible information, even life experiences, by incorporating various philosophical, educational and pedagogical meanings and interpretations.

In the case study of Saint Neophytos the 3D model provides detailed documentation also of the frescoes that exist in the Cell, the Bema and the Naos. According to written testimonies, the Enkleistra was painted in 1183 A.D. by Theodore Apseudes while the final phase of the paintings, mainly in the Naos, belonged to a different phase, after 1197 A.D. The paintings of the Enkleistra were completed and restored in 1503 A.D. through the commission of another monk, called also Neophytos [8, 9, 20].

The iconographical themes that were selected to cover the surfaces of the aforementioned spaces indicate that Enkleistra was meant to act as a “laboratory” for the study of the human soul’s mechanisms and provide pilgrim with valuable pedagogical lessons. The knowledge of these mechanism offers human the capability to intervene upon them, in the pursue of victory upon the soul’s passions and weaknesses. The pedagogical method of Saint Neophytos, which merges the content of the religious scenes with the cave architecture, comprises of three levels that comply with the three distinct zones of the iconographical programme.

The first level of the pedagogical training takes place inside the Cell of Saint Neophytos. In this room, where he was spending his everyday life Saint Neophytos had also engraved his own grave. The constant view of the grave trains the pilgrim about the concept of “death” and the perception of death’s philosophical and spiritual essence. It is not only about the concept of the “inevitable end” of all humans, but furthermore about a training that sets human free, on one hand from the materialistic assets, and on the other hand from his desire to prevail upon other humans. When the pilgrim has reached to that point, then he experiences a grade of freedom that opens up his soul and enables him to profoundly love God.

Inside the Bema takes place the second level of the pedagogical training, due to the representation of Saint Neophytos between two Archangels, unique in the whole byzantine iconography. This representation expresses the loving bond between the human and his love object, namely God. But this road to Love and the unification of human with God is full of traps, deception, plausible phenomena which hide the truth and psychic projections of wishes (alike the projections of an oasis in the dessert), which constitute the “enemies” of the soul. At the same time the way is presented by which a human can cope with the aforementioned situations without damaging his own soul.

The third and last level of the training takes place in Naos. In Naos there are three zones of representations, the position and the general layout of the latter reveals to the eyes of the pilgrim a full life-cycle, through the pedagogical aspect of which the pilgrim can experience a profound spiritual situation.

The lowest zone of the iconographical programme presents ascetics as well as kings, all of them with a halo around their heads, in order to teach that both those who have abandoned the cosmic society and those who have reached the top of social pyramid and governed the world can defeat the human passions and conquer holiness. The presentation of the two opposites, the ones who have nothing (ascetics) and the others who have everything (kings) conveys the message that it is possible for the rest of the people who find themselves in the in-between zone to follow (if wanted) the path of spiritual life and (still) succeed their goals.

The road to reach the ultimate goal (union with God) is represented in the middle zone of the iconographical programme. It is the road of humility. This zone includes scenes from the last days of Jesus Christ, from Holy Wednesday until the Holy Resurrection. It concerns the conscious decision of human to choose forbearance and reconciliation with his co-humans through apologies.

The upper zone is covered by the scene of Ascension of Jesus Christ which is placed on the “roof” of the Naos, extending around the narrow hole that connects Naos with the Hagiasterion, from which Saint Neophytos used to provide the Holy Communion to the pilgrims. In these scenes, the mortal human body of Jesus Christ is lifted up to his Father, to be united with Him (God) and thus be transformed into immortal. In this way Jesus Christ prevailed over death and general decay, which is the success of the unification of humans with God.

Saint Neophytos used to provide the Holy Communion to the pilgrims through the narrow hole on the floor of Hagiasterion. In order for the pilgrims to receive the Holy Communion, they had to climb a ladder towards the narrow hole of Hagiasterion, through which Saint Neophytos was expecting on his knees to provide it to them. During this ascendance the pilgrims were experiencing initially, the approach to the way of life of the people around Jesus Christ in the scene of Ascension, afterwards the approach to Jesus Christ on the cloud presented in the upper zone of the iconographical programme and finally the union with Him through the offer of his body and blood (Holy Communion) executed by Saint Neophytos.

The aforementioned zones of iconographical programme with the architecture of the cave in combination with the service held in the church and the “road” of ascedance of each pilgrim towards the Holy Communion, thus the unification with God, were providing an exceptional pedagogical lesson to the people, through the combined cultivation of the senses, the feelings and the mind.

All the aforementioned aspects regard the intangible information that is incorporated in the monument of Saint Neophytos, which can provide pedagogical content and experiences to those who open up themselves to Christianity. They also serve as input for various educational purposes. The challenge of reusing and creating new digitized cultural heritage content is an issue that concerns scientists, practitioners, professionals and institutions in the field of culture and education. On the one hand, arts and cultural heritage education has been regarded as the key factors in development of the “knowledge society and creative ability” [21]. On the other hand, the ongoing development of ICTs is providing new opportunities of representation and interpretation of cultural heritage. Thus, learning about cultural heritage with the mediation of ICT tools and methods, such as an e-learning platform enriched with multimedia content, can be affective in all educational levels by using appropriately the available ICT affordances [22].

The aim is to engage learners from all ages, underage learners, adolescents as well as vocational trainers. Learning about the culture, the living conditions, the human creations and attitudes in the course of time, understanding the historic-cultural events and the evolution of society, and finally discerning what has survived at the sociocultural surroundings, is the quintessence of arts and cultural heritage education. But in order to achieve the following learning approaches that take under consideration the benefits of using ICTs in cultural heritage education, we need to have a clear image of the range of the “knowledge” by which the present monument is dominated, so we can adjust it to our wide range of target learners. Learning approaches such as: (1) personalized, inquiry-based learning (2) on-site and anywhere learning experiences (3) interdisciplinary learning approaches and (4) collaborative learning experiences, demand prior presence and on-site experiential investigation in order to perceive the inherent value of Saint Neophytos monument, which will become the focus of the (e-)learning course.

An on-site analysis on Enkleistra’s structure and its surrounding place was supplementarily conducted by research team’s multimedia expert, while the required data were acquired through the use of state-of-the-art technological equipment. Moreover, a 360 camera facilitated the wide capture of Enkleistra’s both internal and external landscape on video. The latter one can be used further on in the creation of VR video, while various audio recording devices were put near the cavern in order to capture the sounds caused by touristic engagement. Also, for the purposes of content enrichment several pictures along with video were taken, using not only smartphones with high-resolution cameras but also a UAV (drone) equipped with the latest GoPro 4 camera too. These acquired data will be represented in a digital installation of a physical interactive book, in which the story of Saint Neophytos will unfold before the eyes of readers encouraging them to engage with it using their hands, thus providing an educational approach of the monument’s state. In order to accomplish this, the use of a computer software called VVVV is needed, where advanced programming skills in C# are required for its development.

Targeting at all audiences and lifelong learning experiences that can promote sustainable educational practices, we contribute to the survival of the monument’s ‘memory’ and ‘values’. In addition, by re-using its digital representation of its tangible and intangible aspects in such a context, we further provide its ongoing virtual and oral transmission of its history to the upcoming generations.

3.12 Digital Documentation’s Parameters

As the holistic approach that it is proposed in this paper is digital, a member of the planning and research team is an ICT specialist. Having in mind the 3D models that are produced using survey means as well as their derived data, all the aforementioned set of information will be stored in an SQL relational database taking advantage of DB’s capability in supporting plethora of data types (e.g. integer, chars, floats, strings) constituting it an ideal tool that will act as a reference point for the applications to run effectively. Additionally, this kind of database will be created on Microsoft’s SQL Server, as it runs on programming extensions called Transact-SQL (T-SQL) expanding the common SQL standard to include more functions for the processing of string variables and procedural programming. Moreover, considering the fact that there may be compatibility issues for groups of experts who use open-source technologies, a MySQL database will be further considered as the primary common ground to be used. An important application that will exploit such a DB constitutes the development of an online learning system depicting the cultural significance of Enkleistra using CMS (e.g. WordPress, Joomla etc.) along with PHP code and various plugins enhancing platform’s usability, where users will have the opportunity to be educated through interactive courses that will present the archived data in a user-friendly way. In addition to the proposed website, a mobile application will be considered for development in an IDE like Android Studio taking advantage of JAVA’s capabilities towards the provision of useful information to users regarding Enkleistra’s history and state through the use of 3D models. Assuming the existence of huge amount of data that will be generated over time, the use of data mining techniques to the aforementioned applications will be crucial for their analysis in order to improve their functionality. Towards that end, the collection of sufficient training data is most needed as Artificial Intelligence (AI) has reached a point, where advanced machine learning methods can be implemented in data mining techniques enriching their functionality. The creation of ML scripts that will either be built-in at the code or loaded externally using command(s) will provide the application the ability to “learn” by discovering various patterns that may exist in the data, targeting the enhancement of user experience and the designation of proper preservation methods for Enkleistra.

4 Conclusions and Future Work

A Holistic Documentation Approach to any Cultural Heritage element/monument requires an extensive and interdisciplinary research that considers its tangible and intangible aspects, complimented with a strong reflection in a wide variety of subjects. This is a pioneer approach in current documentation methodologies in the field. ‘Building’ plus ‘memory’, tangible plus intangible, is what transforms a simple structure into a monument, and this is what a holistic digital documentation aims to capture. The Saint Neophytos case study investigates the building’s in-temporality which waits to be deconstructed and constructed again into a new form of communication and will form pilot mechanism for other monuments. The application of a holistic approach can be the key to guarantee the uniqueness of the monument, and the documentation at several levels is the key to protect the cultural values of the place.

The approach followed focused on the documentation and the designation of appropriate preservation methods for the Enkleistra of St. Neophytos monastery, since it is a monument of great cultural significance. The outcome should act as a reference point for the application of restoration techniques that should be applied on Enkleistra’s physical infrastructure in order to limit the risks that threaten its integrity. Nowadays it is difficult to finance these methods due to the economic crisis that exists in the Mediterranean countries, however an important measure that should be taken into consideration is the listing of Enkleistra on UNESCO’s World Heritage Catalogue as a cultural heritage site of outstanding universal value from historical point of view by meeting certain criteria that should apply on its tangible form [23], leading this way in the raise of both domestic and global awareness towards its protection and conservation.

As technology has entered rapidly in peoples’ daily lives, there are various digital online learning systems aiming to disseminate both tangible and intangible significance of historical monuments that are mentioned on UNESCO’s World Heritage Catalogue. An online educational tool, created by [22], provides a new way of reusing Cultural Heritage data obtained from image-based and 3D modelling, terrestrial laser scanning techniques, photogrammetry methods etc. which could also be applied in St. Neophytos case. The proposed platform includes interactive lessons and activities using 3D representations of the cavern, where internet users are taught monuments’ historic background in various multimedia ways (by solving digital puzzles that reenact hagiographies, watching dramatized videos that present the key elements of the monument). At the end of each lesson, users are asked to answer few comprehensive questions regarding the undertaken course awarding them with a ready-to-print statement of accomplishment. These online interactive courses could assist users in acquiring a better understanding of the existing risks that threaten Enkleistra’s integrity. Furthermore, informative dissemination, such as publications, books, exhibitions, as well as re-creation of case study’s digital content through 3d printing, screening, modeling, etc., will be helpful in the direction of raising public awareness about the monument and the necessity for its immediate conservation.

Although the expected increase of cultural tourism may constitute a beneficial side of raising awareness, it stimulates issues regarding its preservation as there are plenty of tourists that would like to interact with the already damaged hagiographies creating this way more detriment and degeneration on their surface. Fortunately, the use of Virtual, Augmented and Mixed Reality technologies have reached a point of evolution where they can offer realistic and interactive experiences to humans. Aiming at the decrease of touristic engagement inside the cave, an exploitation of these technologies can be achieved. More specifically, visitors would be “transferred” into a virtual representation of the cave where the Saint spent all of his life and could interact with the digital frescoes in a way that is both engaging and educational through their participation in game(s), where they would be asked to fill the missing hagiographic segments in order for St. Neophytos to “come alive” and recite his story. Towards the aforementioned, an interactive analogue book can be located in the monastery’s entrance where tourists may experience another form of educational environment grasping all the multimedia data (images, texts, 3D, videos etc.) that thrive from the monument while at the same time would be presented in a user friendly way.

Last but not least, creation of software and storage of the extracted cultural data along with its semantic interrelations, can be used in collaboration with modern advanced information systems like HBIM in depicting the optimal methods that can be exploited towards Enkleistra’s preservation. This kind of management system can act as a reference point for the holistic digital documentation of this monumental cave, providing reverse engineering data to professionals from multidisciplinary areas that work together in the protection and preservation using detailed 3D models. By this way, academic research between various disciplinary sectors will be assisted too, and links with other methodological approaches and practices for monuments of similar characteristics or of common elements can be established.