| ■Tokyo National Research
Institute for Cultural Properties |
■Center for Conservation
Science |
| ■Department of Art Research,
Archives and Information Systems |
■Japan Center for
International Cooperation in Conservation |
| ■Department of Intangible
Cultural Heritage |
|
The terraces in front of the Central Complex (Cruciform Terrace is highlighted in red)
Excavation at the Cruciform Terrace
Conservation of the Central Tower's original stone members
Ta Nei Temple is a Bundist temple estimated to have been built during the period from the end of the 12th to early 13th century. A large rectangular terrace and a Cruciform Terrace are aligned at the eastern side of the Central Complex, which is the front side of the Temple. While a large terrace is often set in front of the building complex in the other temples of the same period, the style connecting a cruciform terrace in front of a rectangular terrace is unique. Therefore, these are considered important remains, when we think about the characteristics of Ta Nei Temple. However, as tree roots had grown on the terraces and the soil infill layer inside the terraces had unevenly subsided, the terraces had largely collapsed, especially the Cruciform Terrace.
Therefore, the Japan Center for International Cooperation in Conservation dispatched four staff members from the end of November to late December 2024 and started an excavation of the Cruciform Terrace as a preliminary investigation for future discussion on the conservation and restoration methods, working with the archeological staff of the Authority for the Protection and Management of Angkor and the Region of Siem Reap (APSARA) of the Cambodian government. At the same time, surveys on internal structures, damage, and remaining status of fallen stone materials were conducted and fundamental discussions related to the direction of future restoration were held.
As a result of the excavation, many scattered stone materials that could be considered to have formed the Cruciform Terrace were detected under the accumulated soil around the Terrace. Furthermore, some parts of the foundation work layer and the internal structure of the Terrace were revealed. When we investigated the current level of the Terrace foundation, some subsidence was observed toward the ends of southern and northern wings, but the foundation itself remained in relatively good condition. On the contrary, it was confirmed that the side walls and floor materials were lost in many areas and that, as a result, an inner infill mainly consisting of sand had flowed out at the southern and northern sides of the eastern wing and around the southern wing of the Terrace. Almost no materials that can be estimated to have been used for the middle layer of the side walls of the Terrace were found, which could suggest that these stone materials were taken away intentionally during some past era(s). Based on these observations, we discussed the restoration methods of the Cruciform Terrace with APSARA staffs and mostly agreed on a basic direction and future plan for the restoration.
Simultaneously, we conducted some additional conservation work of stone materials at the eastern and western entrances of the Central Tower. Partial restoration of these areas had been ongoing until August 2024 (Field Activities Parts XVI to XVII). In addition, during the mission, meetings of the International Coordinating Committee (ICC-Angkor/Sambor Prei Kuk) were held in Siem Reap City from December 11 to 13. We reported on the completion of restoration of the entranceway of the Central Tower and the investigation on the Cruciform Terrace in front of the Central Complex.
Investigation of flood damage in Barbar temple
Symposium on Al Faw Archaeological Area
The Japan Center for International Cooperation in Conservation sent a research team to Bahrain and Saudi Arabia to take part in investigation and discussion of the preservation of cultural heritage in early October.
A tripartite memorandum of agreement had been signed among the Bahrain Authority for Culture and Antiquities, the Tokyo National Research Institute for Cultural Properties, and the Institute for the Study of Ancient Civilizations and Cultural Resources at Kanazawa University. Together they launched a research center to promote archaeological studies in Bahrain and cultural heritage preservation projects in collaboration. The purpose of this visit was to investigate the current preservation conditions of cultural heritage that had been damaged by heavy rain in the beginning of this year. In Qalat al Bahrain, collapse of the outer walls of the fort by water damage and serious bending of the ceiling beams made from palm trees were recognized, and the site was temporarily closed to the public. Additionally, soil erosion was recognized in a well thought to be the most sacred part of the Barbar temple, and several stones were inclined or moved by the water flow. Effects on the cultural heritage due to increasing annual precipitation is becoming more serious year by year across the Middle East. We proposed to periodically monitor the progression of deterioration in comparison with the past situation, and discussed immediate countermeasures to reduce flood damage.
We attended a symposium held in Riyadh that focused on the Al Faw Archaeological Area in Saudi Arabia, which had just been newly inscribed on the UNESCO World Heritage List in September 2024, and then visited the archaeological site. Excavation has been completed only by a few percentages, as the Al Faw Archaeological site is large and complex, mainly composed of a pre-Islamic caravan city, and also includes an area of ritual practice and numerous mound tombs from the Bronze Age. We also had a meeting with the Heritage Committee of the government of Saudi Arabia, and agreed to continue discussions on a partnership to promote site management and research for a future public opening of the Al-Faw Archaeological Area.
West entrance of the Central Tower before and after restoration (3D model created by Photogrammetry)
Stone conservation
Located in the northeastern area of the Angkor Monuments, one of the World Heritage Sites in Cambodia, Ta Nei is a Buddhist temple thought to have been built in the late 12th to early 13th century. Its Central Tower, about 15 meters high, is partly collapsed, but still has pediments with carved Buddhist motifs on all sides and a pedestal inside on which the main Buddha image is thought to have been placed.
The entrance frames on each side are made of sandstone, but the upper frames on both the east and west sides are broken and deformed, and they had been supported by wooden supports. During this visit, we carried out partial restoration work on the entrance components to structurally stabilize the east-west entrance of the Central Tower and to remove the wooden supports so that visitors can safely walk along the central axis of the temple while viewing the temple as its original appearance.
Prior to the restoration work, the restoration plan was proposed and approved at the international meeting of ICC-Angkor/Sambor Prei Kuk in March 2024 (see previous article here). Subsequently, the work began in June under the leadership of the Authority for the Protection and Management of Angkor and the Region of Siem Reap (APSARA). As part of its technical cooperation for this restoration project, the Tokyo National Research Institute for Cultural Properties (TOBUNKEN) dispatched two staff members (XVI field survey) from June 15 to July 2, 2024, and one staff member (XVII field survey) from August 7 to 11, 2024, for collaborative work with the APSARA staff. Specifically, the following procedures were followed: (1) dismantling and recording the sand stones composing the entrance and scattered stones in the surrounding area, (2) partial dismantling of the doorframes, (3) stone restoration, (4) reassembling, and (5) recording after restoration, which was successfully completed when the staff was dispatched in August.
Examination of structural members by master carpenters and staff from both Japan and Bhutan
The Lham Pelzom house
Since 2012, the Tokyo National Research Institute for Cultural Properties (TOBUNKEN) has been continuously engaged in research on vernacular houses in Bhutan, in collaboration with the Department of Culture and Dzongkha Development (DCDD), Ministry of Home Affairs, Royal Government of Bhutan. The DCDD promotes a policy of preserving and utilizing vernacular houses by integrating them into the legal protecting framework of cultural heritage, while TOBUNKEN supports the initiative from academic and technical aspects.
The Lham Pelzom house, located in Kabesa near the capital of Thimphu, is considered the oldest among about eighty vernacular houses that we have surveyed across Bhutan. This house is enclosed with rammed-earth outer walls that have few openings. Because it has very different characteristics from the current ordinary houses in Bhutan, we assume that it was built at the latest in the 18th century or earlier.
At the time of our initial survey in 2013, this house was already dilapidated. In 2017, the wooden parts, including the roof and floor of the upstairs, completely collapsed. Coping with this situation, the structural members scattered in the house were collected and stored, and a temporary roof was constructed to preserve the remaining structure of the outer walls. During the COVID-19 pandemic we could not conduct on-site activities, and the Bhutan side continued with the procedures to obtain cultural heritage status designation of this building. As a result of those efforts this house was successfully designated as a cultural heritage site in 2023, the first time for a vernacular house.
We dispatched four people, including two TOBUNKEN staff and two external experts from Japan, from August 12 to 23, 2024. The team surveyed the structural members as part of the restoration planning for this vernacular house with local staff, including DCDD officials. Dr. Alejandro Martinez, Associate Professor of Kyoto Institute of Technology, who had previously taken part in storing the members, worked to identify where each member was originally used. Mr. TOBASE Koji, master carpenter and Chairperson of the Japanese Association for the Conservation of Techniques for Traditional Architecture who experienced many restorations of traditional Japanese wooden buildings, examined each member for its reusability and discussed its restoration methodology. Nine Bhutanese master carpenters who are engaged in restoring historical buildings joined the activities. During the surveys, we were visited by H.E Mr. Tshering, Home Minister of Bhutan, and interviewed by the national TV station and a newspaper. This project attracts strong interest in Bhutan. We are continuing to carefully work on the overall restoration plan, considering the maximum conservation of its authenticity, and to support the tasks including the restoration cost calculation for securing the production budget on the DCDD side.
The surveys were conducted with the support of a JSPS Grant-in-Aid for Scientific Research (B) “Vernacular Stone Masonry Houses of Bhutan: A Study on the Architectural Characteristics and the Suitable Approach for Protection as Cultural Heritage” (Principal Researcher: TOMODA Masahiko).
Survey at Sakteng village
Devastating remains of a manor house (Phongmey Nagtshang)
Since 2012, the Tokyo National Research Institute for Cultural Properties (TOBUNKEN) has been continuously engaged in research on vernacular houses in Bhutan, in collaboration with the Department of Culture and Dzongkha Development (DCDD), Ministry of Home Affairs, Royal Government of Bhutan. The DCDD promotes a policy of preserving and utilizing vernacular houses by integrating them into the legal protecting framework of cultural heritage, while TOBUNKEN supports the initiative from academic and technical aspects.
We conducted the first field survey for FY 2024 from May 11 to 23. For this purpose, three staff members of TOBUNKEN and two external experts from Japan were dispatched. Together with two DCDD officials, we surveyed mainly stone masonry houses in two eastern Dzongkhags (provinces): Trashigang and Trashiyangtse.
The current survey area included three villages that we had visited from April to May 2023 for the supplemental survey, in addition to three villages that were new for us.
In the Kheni village of Trashiyangtse Dzongkhag, where we visited first, we completed a detailed survey on all of five houses considered as very old in the village, including measurement taking and interviews with the residents of the houses. For three of the houses that had been surveyed last year, supplemental surveys were conducted. The other houses were also fully surveyed.
Next, at Merak and Gengo villages in Merak Gewog of Trashigang Dzongkhag, we conducted a supplemental survey on one house and new surveys on six other houses. All of these houses are single-story buildings with main entrances on the gable side. Many of them have a living room with partial wooden outer walls at the front side of the attic level. This building type is peculiar to these areas in which transhumant ethnic minorities live. In the survey on such regionally-unique-style houses, we identified 67 houses across Merak village, and revealed that around half of the houses, especially those in the center of the village, were in this style.
We then visited Sakteng Gewog of Trashigang Dzongkhag for the first time, where the same ethnic group lives. We confirmed that a similar style of houses to that of Merak existed there. However, as some of those houses were surrounded by stone fences with gates, the scenery inside the village was very different. We conducted detailed surveys of five houses in total in both adjacent Sakteng and Tengma villages. We managed to collect valuable examples, including small houses built totally of wood and water mills for producing flour. The living area of the same ethnic group expands to the neighboring Northeastern region of India. We are informed that houses of similar styles exist there, in which we are very much interested.
Additionally, we surveyed two old houses of feudal lords in Phongmey village in the same Dzongkhag. Both of them were no longer in use. One of them was severely damaged with largely deformed stone walls and in a risky condition. There is concern that such case can rapidly increase due to the depopulation in countryside. Even though it is difficult to take immediate conservation measures, it is at least required to grasp and document the locations and current situations of these old houses.
The surveys were conducted with the support of a JSPS Grant-in-Aid for Scientific Research (B) “Vernacular Stone Masonry Houses of Bhutan: A Study on the Architectural Characteristics and the Suitable Approach for Protection as Cultural Heritage” (Principal Researcher: TOMODA Masahiko).
Protection work of the Terrace on the West Embankment of the East Baray
Site inspection by the ad-hoc experts
The excavation of the Terrace on the Embankment at the easternmost end of Ta Nei Temple was reported in a previous article. As a continuation of that report, here we summarize the protection work on the terrace that was carried out from March 8 to 29, 2024.
This terrace was built from the top to the east slope of the west embankment of the “East Baray,” one of the huge reservoirs that characterize the Angkor Monuments. Therefore, it was an urgent task to protect the laterite stones from being washed away during the rainy season, especially those that were situated on the sloping terrain. First, four stones that had been moved from their original position and were structurally unstable were re-positioned. The perimeter of the stones on the slope was also reinforced with a compacted lime-mixed earth mortar, known as ‘lime mortar.’ The excavated area on the top of the embankment was also backfilled, particularly around the perimeter of the terrace, where there is concern about movement due to rainwater. Further work will be carried out in the future to cut down trees around the terrace, which is one of the factors causing the collapse of the structure.
From March 14 to 15, an international meeting of ICC-Angkor/Sambor Prei Kuk was held, at which each team reported on their restoration projects. The Tokyo National Research Institute for Cultural Properties (TOBUNKEN) and the Authority for the Protection and Management of Angkor and the Region of Siem Reap (APSARA) jointly reported on the progress and future plan for the conservation of Ta Nei Temple. Prior to this meeting, on March 8, ICC ad hoc experts responsible for providing technical recommendations on each restoration project visited the site. The future restoration and maintenance policy, including the restoration of the east and west entrances to the Central Tower, which is scheduled to be carried out in 2024, was explained at the site, and the plan was approved.
Visiting the Historic Sites: Korokan Historical Museum
Under a cooperative project between the Authority for the Protection and Management of Angkor and the Region of Siem Reap (APSARA) and Tokyo National Research Institute for Cultural Properties (TOBUNKEN), restoration work of the East Gate of Ta Nei Temple in Angkor in Cambodia was completed in November 2022.
To commemorate the completion of the restoration, a technical exchange program* was organized by TOBUNKEN, including the invitation of three experts from Cambodia to Japan: Mr. Kim Sothin (Deputy Director General, APSARA), Mr. Som Sopharath (Director of Department of Conservation of Monuments and Archeology, APSARA), and Mr. Sea Sophearun (Technical Officer, National Authority for Sambor Prei Kuk).
Following an open seminar, “Seminar commemorating the completion of the Restoration of the East Gate of Ta Nei Temple,” held on February 14 at TOBUNKEN, a study tour was conducted from February 15 to 18, in which the following conservation sites of the nationally designated Important Cultural Properties and Historic Sites were visited: the former Alt residence, the former British council, Shofukuji-Temple in Nagasaki city, and Korokan Historical Museum in Fukuoka city.
Experts from both countries who are engaged in heritage conservation research and fieldwork participated in enthusiastic discussions during the seminar and study tour. This proved to be a valuable opportunity for deepening mutual understanding of various areas, including heritage value, preservation techniques, presentation methods, and more.
*This program was partially funded by the Foundation for Cultural Heritage and Art Research, Japan.
A historic building damaged, collapsed, and temporarily closed. (Hatay)
Restoration of the collapsed walls is underway at Gaziantep Castle.
Experts' seminar
The Tokyo National Research Institute for Cultural Properties (TOBUNKEN) participated in the Emergency International Contribution Project for Cultural Heritage in FY2023 commissioned by the Agency for Cultural Affairs, Government of Japan, which was titled as “Project for supporting the Reconstruction of Damaged Cultural Heritage in Türkiye,” in cooperation with the Cultural Heritage Disaster Risk Management Center, Japan (CHDRMC).
The primary objective of this project was to provide relief support for museums and cultural heritage damaged in the 2023 Türkiye–Syria earthquakes that occurred on February 6, 2023. In addition, by sharing Japan’s experience in rescuing damaged cultural heritage and our accumulated knowledge of cultural heritage disaster prevention with Türkiye, the project also aims to support the establishment and enhancement of a cultural heritage disaster prevention system in Türkiye.
From November 28 to December 7, 2023, a joint team of TOBUNKEN and CHDRMC visited Türkiye to investigate the affected areas, exchange information on cultural heritage disaster prevention in both countries, and exchange opinions with their Turkish counterparts for future collaboration.
The team visited museums and cultural heritage sites in Hatay, Gaziantep, and Şanlıurfa to ask museum staff about the response to the disaster, the current situation, and other issues, and to survey future support needs. At present, emergency measures are almost completed at the damaged museums, and full-scale work for recovery of the damaged collections and buildings is expected to be carried out in the near future. The museum in Şanlıurfa was flooded by heavy rains in early March, one month after the earthquake.
The experts’ meeting was held at the Ministry of Culture and Tourism, Republic of Türkiye, jointly with the Ministry. The Japanese side provided an overview of cultural property disaster prevention systems in Japan, and reported on activities to rescue cultural properties damaged in the Great East Japan Earthquake and other recent disasters, as well as disaster prevention measurements at museums. The Turkish side reported on the damage to cultural properties caused by the earthquake, presented an overview of the response, and discussed disaster risk mitigation methods at museums. The parties from the two countries are continuing with further discussion regarding the direction of specific mutual collaboration and promotion of joint research on cultural property disaster prevention.
Survey scene at an old house
A vernacular house in which rammed earth and stone masonry structures coexist.
Since 2012, the Tokyo National Research Institute for Cultural Properties (TOBUNKEN) has been continuously engaged in research on vernacular houses in Bhutan, in collaboration with the Department of Culture and Dzongkha Development (DCDD), Ministry of Home Affairs, Royal Government of Bhutan. The DCDD promotes a policy of preserving and utilizing vernacular houses by integrating them into the legal protection framework of cultural heritage, while TOBUNKEN supports the initiative from academic and technical aspects.
Following the previous survey conducted in the eastern region from April to May 2023, the second field survey mission of this year was implemented from October 29 to November 4. Four staff members of TOBUNKEN, one from Nara National Research Institute for Cultural Properties (NABUNKEN), and two external experts were dispatched, and the team was joined by two staff members from DCDD. We jointly carried out a field survey in the two provinces of the central region, namely Bumthang and Wangdue Phodrang.
Most of the target houses had been identified in our preparative survey conducted in 2022. Eleven houses in total, including those newly found, were investigated this time in a detailed manner that included taking measurements and interviewing the residents. Two houses among them were rammed earth houses commonly seen in the western area of the country, and six were stone masonry houses widely located in the eastern area, while both construction techniques were combined in the other three houses. Especially in the eastern part of Wangdue Phodrang province, a tendency had been observed that the rammed earth technique was exclusively used further in the past, and stone masonry has gradually become dominant over time. However, our analysis of the transitional history of each house suggests that things were not so simple, and present more complex pictures.
On the other hand, although we had been focusing on such aspects as building type, construction technique, and transitional history of the houses, this time during the interviews we started to pay more attention to ethnographic factors such as oral traditions about houses and how each room is used. By adding information about villager’s lifestyles, which reflected on the transition and locality of the housing type, into our consideration, hopefully diverse values of the Bhutanese traditional houses as cultural heritage will become clarified.
The survey was implemented with the financial support of a JSPS Grant-in-aid for Scientific Research (B), “Vernacular stone masonry houses of Bhutan: study on the architectural characteristics and the suitable approach for protection as cultural heritage” with TOMODA Masahiko as the principal researcher.
Excavation of the Terrace on the West Embankment of the East Baray
The newly installed (left) and the existing (right) supports at hazardous spots inside the East Tower of the Central Complex
Ta Nei Temple is located facing the East Baray, one of the huge reservoirs that used to supply water for the Angkor capital. The terrace at the eastern end of Ta Nei Temple was built on top of the West Embankment of the East Baray, being not only significant as the main entrance of the temple, but also connected to the other temples through the Embankment. However, due to the extremely poor condition of the terrace, its construction period and structural features have remained uncertain.
The Tokyo National Research Institute for Cultural Properties has so far conducted excavation of the terrace in three periods: November 2017, March 2018, and August to October 2018, aiming to delineate the plan of the terrace and consider the intention of construction. These previous surveys revealed plans of the terrace, especially the structure of the west wing. In this term, four staff members were dispatched from November 5 to 30, 2023 to carry out archaeological and architectural studies to understand the northern and the southern sections of the terrace as well as the construction process, in cooperation with Authority for the Protection and Management of Angkor and the Region of Siem Reap (APSARA).
Although traces of the stone masonry structure at the northern and southern sections of the terrace were scarcely identified, the excavation provided some clues to enable estimation of the original construction process of the terrace based on stratigraphical analysis of the mound structure. Additionally, a structure made of stones and bricks, which appears to be the foundation of a wooden pillar, was discovered on the surface of the terrace. Those remains indicate that a wooden structure was presumably built on the terrace at a certain time of its history. A level directly below where many roof tile fragments were unearthed by this excavation is thought to be the ground surface at the time when the wooden structure was built on the terrace. The details of the structure of the terrace still have not been ascertained, requiring further investigation.
In addition to the above-described investigation of the terrace, we conducted minor repair work on the East Gate that had been completed last year, and continued its documentation. Moreover, we installed additional supports at hazardous spots inside the East Tower of the Central Complex, and held on-site meetings to discuss future collaborative activities at the temple.
Remarks of His Majesty Preah Bat Samdech Preah Boromneath Norodom Sihamoni, King of Cambodia
Reporting on the conservation and sustainable development project of Ta Nei Temple
On November 15, 2023 Ms. KUROIWA Chihiro, Associate Fellow of the Japan Center for International Cooperation in Conservation, attended the “4th Intergovernmental Conference for the Safeguarding and the Development of Angkor” held at UNESCO Headquarters in Paris, France.
In 1992 following the end of the Cambodian Civil War, Angkor Monuments were inscribed on the World Heritage List, but at the same time, they were also placed on the List of World Heritage in Danger. At the first intergovernmental conference held in Tokyo in 1993, co-chaired by Japan and France and attended by 30 countries and 7 international organizations, the “Tokyo Declaration” was adopted calling for international cooperation towards safeguarding the monuments and sustainable development of the surrounding area. In the same year, the International Coordinating Committee for the Safeguarding and Development of the Historic Sites of Angkor (ICC-Angkor) was established to formulate technical guidelines and evaluate the activities of international conservation teams.
The Intergovernmental Conference takes place every 10 years to review and evaluate the ICC-Angkor and to discuss the policies for future conservation and sustainable development. The second conference was held in 2003 (France), the third in 2013 (Cambodia), and the fourth was held this time in Paris. In the past 30 years, numerous international projects for restoration and conservation have been implemented at the Angkor Monuments and Sambor Prei Kuk, another World Heritage Site.
His Majesty Preah Bat Samdech Preah Boromneath Norodom Sihamoni, King of Cambodia, H.E. Ms. Audrey Azoulay, Director General of UNESCO, H.E. Ms. Rima Abdul-Malak, Minister of Culture of the French Republic, Mr. KOMURA Masahiro, Parliamentary Vice-Minister for Foreign Affairs of Japan, and other international members attended the conference. During the technical session, presentations were made by teams from various countries involved in the conservation of Angkor and Sambor Prei Kuk monuments. We also reported on the collaboration with APSARA for the conservation and sustainable development of Ta Nei Temple.
Kheni village in Trashiyangtse province, composed of vernacular stone masonry houses
A house of typology unique to Merak district in Trashigang province
Measurement survey of a timber hut
Since 2012, the Tokyo National Research Institute for Cultural Properties (TOBUNKEN) has been continuously engaged in research on vernacular houses in Bhutan, in collaboration with the Department of Culture and Dzongkha Development (DCDD, formerly the Department of Culture, renamed recently upon restructuring), Ministry of Home Affairs, Royal Government of Bhutan. The DCDD promotes a policy of preserving and utilizing vernacular houses by integrating them into the legal protection framework of cultural heritage, while TOBUNKEN supports the initiative from academic and technical aspects.
Previously, our study focused on rammed earth houses commonly seen in the western area of the country. This year, we began a survey on stone masonry houses widely located in central and eastern areas, with the financial support of a JSPS Grant-in-aid for Scientific Research. The first survey mission under this scheme was implemented from April 25 to May 5, 2023.
Our group, comprising four dispatched staff members of TOBUNKEN and two from DCDD, jointly carried out a field survey in the five provinces spanning from Trashigang in the east to Bumthang in the central region. We observed stone masonry houses that appeared to have been built during earlier periods than other traditional houses in the target area, based on prior information collected by DCDD, and surveyed 14 houses in a detailed manner including taking measurements and interviewing the residents. Other than three cases of large-scale, three-storied residences of the ruling class, all were originally very small houses of one or two stories. In the Merak district of Trashigang, where a nomadic ethnic group lives, a unique typology of one-story houses without cattle sheds was widely observed.
Based on knowledge and information obtained during this survey mission, we plan to extend the target area and conduct more detailed investigations of the old houses we had already identified. In addition, since transition and locality of the housing type reflects change and difference of lifestyles, we feel a need to put more focus on these areas in the future. We will continue in our effort to further accelerate cooperation to prevent the loss of precious heritage against the trend that the numbers of vacant and degraded houses are increasing.
APSARA dance performed in the ceremony
Poster exhibition (TOBUNKEN poster is in the middle)
The Tokyo National Research Institute for Cultural Properties (TOBUNKEN) has been working with the Authority for the Protection and Management of Angkor and the Region of Siem Reap (APSARA) on the cooperation program for the Ta Nei Temple in the Angkor Archaeological site in Cambodia.
Angkor was inscribed on UNESCO’s World Heritage List in 1992. This led to comprehensive international support and cooperation from other countries, including Japan, which covers not only the conservation and restoration of the archaeological sites, but also various other fields like the formation of management systems, including human resource development, tourism development, and planning and infrastructure improvement for sustainable development of the surrounding regions. Angkor has been established as a top international tourist destination and became one of the most important sources of foreign currency revenue for the Cambodian economy. At the same time, it was highly praised as a successful model of international cooperation on the protection and utilization of World Heritage Sites, despite facing various challenges till date.
On the early morning of December 14th, 2022, I attended a ceremony commemorating the 30th anniversary of Angkor’s inscription on the World Heritage List. The solemn ceremony, held in front of the entrance causeway to the Angkor Wat Temple, started with Buddhist sutra chanting by many priests, where the APSARA dance was also performed. A poster exhibition on international cooperation history, including TOBUNKEN’s projects, was also held at the event.
On the following two days, the 36th Technical Session and the 29th Plenary Session of the International Coordinating Committee for the Safeguarding and Development of the Historic Sites of Angkor and Sambor Prei Kuk (ICC-Angkor) were held successively in Siem Reap City. For the previous two years, these regular meetings were held online due to the COVID-19 pandemic. This year, we finally managed to hold the meeting in person, with related experts and institute representatives both from and outside of Cambodia. The progress on many programs was reported and shared, and we revived the relationship among the related parties from various countries. I deeply appreciate the fact that in-person meetings as precious opportunities have finally resumed.
Arial view of Korphu village (from the west)
MoU signing ceremony (left: Director of the Japan Center for International Cooperation in Conservation, TOBUNKEN, TOMODA Masahiko; right: Director-General of the DoC, Nagtsho Dorji)
From the scientific research aspect, the Tokyo National Research Institute for Cultural Properties (TOBUNKEN) provides technical support for the value evaluation and enhancement of heritage buildings to the Department of Culture (DoC), the Ministry of Home and Cultural Affairs of Bhutan, which aims to expand the scope of heritage conservation to all historic buildings, including traditional houses. While we have been forced to implement cooperation projects online since January 2020 due to the worldwide COVID-19 pandemic, TOBUNKEN agreed with the DoC to resume joint surveys in Bhutan, following the significant easing of travel restrictions in Japan and Bhutan from July and September onward, respectively. From November 5th–15th, 2022, TOBUNKEN dispatched four staff experts, including an expert from the Nara National Research Institute for Cultural Properties.
The mission targeted the traditional masonry houses found in the eastern part of Bhutan. The purpose was to recognize and analyze the fundamental features of settlements and buildings in the region as the preliminary stage of the comprehensive scientific survey, which will serve as the basis for appropriate heritage conservation and development. Effective survey strategies were also examined in the mission. The on-site survey covered Trongsa Dzongkhag, Bumthang Dzongkhag, and the surrounding area, located in the central-eastern part of the country, which is relatively easy to access from the capital city of Thimphu. Measurements, photogrammetry, and interviews with locals were conducted in villages and houses preselected by the Division of Conservation of Heritage Sites (DCHS) of the DoC, based on the governmental archive and information provided by Dzongkhags. We found that the region had its own distinctive village forms. For instance, Trong and Korphu, located in the rugged mountainous area in the southern part of Trongsa Dzongkhag, are particularly unique as their houses are built in rows along a ridge, giving them merchant town-like appearance despite them being farming villages. In addition, while almost all houses in Trong are masonry structures, those in Korphu are both masonry and rammed earth structures, and rammed earth structures retain their older form. In other houses we surveyed, some were originally built in rammed earth, and later expanded or modified in stone. This suggests that, at least in the region surveyed this time, the structural manner of traditional houses shifted from rammed earth to masonry. We also found some masonry houses that have a very complex series of expansion and modification, and there is a possibility that the frequency of modification is generally higher in masonry structures than that in rammed-earth structures. Regarding the survey method, photogrammetry proved to be efficient and very useful in recording the masonry house, which shows random and complex patterns with natural stones and has many distortions in its shape.
After the on-site survey, a Memorandum of Understanding (MoU) for the cooperation in the conservation of architectural heritage was signed at the DoC headquarters, Thimphu, and a meeting was organized with the DCHS to discuss the results of the survey, as well as the prospects and needs of the Bhutanese counterparts. In the future, we expect to develop more on-site surveys and research activities targeting masonry houses in eastern Bhutan in close collaboration with the DCHS.
Symposium
Hanoi was previously called Thang Long and has been the capital of Vietnam most time since the establishment of the Lý dynasty – the first Vietnamese independent and unified nation at the beginning of the 11th century. The Imperial Citadel of Thang Long was where a group of imperial palaces, serving as both the emperor’s residences and the political control base, were located. The original palace remains were considered lost because the site was turned into an army facility in the modern age, while it was known that the palaces used to exist at the location.
However, the many remains, such as the foundations of the original palaces and related artifacts in each dynasty, including those from the Lý dynasty, were unearthed by a large-scale excavation investigation beginning in 2002, which was associated with the rebuilding of the Parliament House Building. This partially revealed how the Thang Long palaces used to be, although they were hidden for a long time. It was decided to conserve this site and it was inscribed on the World Heritage list in 2010, the 1,000th anniversary of the establishment of the capital. Responding to the request of the Vietnamese government, Japan has been cooperating in the research and conservation of this heritage since 2006. I had the responsibility of supporting architectural study and conservation management, as well as the overall implementation of this cooperation program from 2008 to 2013.
International Symposium: 20 Years of Research, Conservation and Promotion of the Values of Thang Long Imperial Citadel Heritage Site was held at the site co-sponsored by the Hanoi People’s Committee and UNESCO Ha Noi Office on September 8th and 9th, 2022, the 20th anniversary of the commencement of its investigation. Many representatives from governmental organizations, UNESCO, ICOMOS, and ICOM, and experts from and outside Vietnam participated and shared the research outcomes in each field. They also provided over 20 reports and conducted discussions regarding the challenges toward its future conservation and utilization. I made a presentation titled International Cooperation between Japan and Vietnam for the Conservation of Thang Long Imperial Citadel Site and also played the role of a commentator at a discussion.
Some have wished for some time now to reconstruct the Kính thiên palace, the main building, on the existing foundation of the later Lê dynasty (16th century or later). Several reports concerning the materials indicating reasonable grounds for the reconstruction were provided, and the study progress was stressed at this symposium. On the other hand, as the former military headquarters from the French Colonial period stand on this foundation and its front, it is necessary to demolish or relocate these buildings to reconstruct the palace. However, these buildings, founded later, are exactly parts of evidence indicating this heritage’s longevity and a layered record of vestiges identified as the World Heritage Outstanding Universal Value (OUV). Therefore, it is difficult to reconstruct the palace without OUV modification. Later, at the symposium, this topic was discussed in detail and it became the focus of discussion. After these in-depth discussions, the proposal of the Heritage Site Management Plan, including this reconstruction plan, was shelved, and the discussion summary to continue the discussion regarding the reconstruction of the Kính thiên palace was adopted.
While the cooperation program between Japan and Vietnam has been completed, I will closely monitor the conservation management movement of this heritage site.
Retouch work on the East Gate after restoration
Archeological investigation for digging a temporary ditch around the East Gate
Areas at risk on the East Tower Shrine of the central building complex: emergency replacement of reinforcements
The Tokyo National Research Institute for Cultural Properties (TOBUNKEN) continues to support the conservation and sustainable development project of Ta Nei Temple by the Authority for the Protection and Management of Angkor and the Region of Siem Reap (APSARA) in Cambodia. We dispatched three expert members from June 12th to July 3rd, 2022. The mission aimed to supervise the finishing works for the restoration of the East Gate, conduct archaeological investigations for setting a new drainage ditch from around the East Gate, and survey the areas at risk of the central building complex.
For the East Gate restoration, in May, the APSARA team began retouching the parts identified at our previous dispatch in January 2022. We assessed their working status and further discussed how to deal with the broken part of stones and finish the surface with sculptures, and other aspects with APSARA. Although this resulted in additional work, we almost completed the given work by the end of June.
Furthermore, the water drainage around the East Gate had been an outstanding issue. In discussions with APSARA, it was decided to cut a temporary drainage ditch from the west side of the East Gate to the North Moat. We tasked Mr. KAHSHA Hiroo, a visiting researcher, with conducting archeological investigations related to a new drainage ditch set-up. We dug up a ditch carefully, to avoid damaging the original land surface at the time of constructing the East Gate and the Cruciform Terrace, and completed an approximately 30-meter-long temporary drainage ditch. We plan to carefully monitor its effect during the rainy season until October, in cooperation with on-site staff.
In the central building complex, we investigated the areas at risk in detail by scaffolding around the buildings of the Central Tower and the East Tower Shrines, which were identified as the highest priority for safety measures based on the discussions with the APSARA risk map team. Because the old wooden reinforcements in the areas at risk were severely deteriorated by pest damage and other factors, replacements using durable materials had been requested for some time. Following APSARA’s request, it was decided to tentatively replace the wooden reinforcements with scaffolding tubes and couplers. We renewed the reinforcements in a part of the Central Tower Shrine and three parts of the East Tower Shrine. We, in discussions with APSARA staff, tried to pursue minimum intervention while carefully examining lacking areas or cracks in the stone materials caused by imbalanced load transfers. Furthermore, safety measures were implemented by setting temporary fences along visitor routes to prevent tourists from entering the areas at risk.
We also held a working session with the Department of Tourism Development and Culture of APSARA as they planned biking tours around the area, including Ta Nei Temple. We exchanged ideas about the development of tourist facilities and discussed measures to protect the ruins, secure the visitors’ safety, and enhance visitors’ understanding of the ruins. We aim to further discuss effective ways to achieve balance between the appropriate protection and tourism for this site.
Onsite survey after the restoration of the East Gate
Survey for the risk parts of the central building complex
Tokyo National Research Institute for Cultural Properties (TOBUNKEN) has been engaged in technical cooperation for the conservation and sustainable development project of Ta Nei Temple by the Authority for the Protection and Management of Angkor and the Region of Siem Reap (APSARA) in Cambodia. While it had been difficult to visit the site due to the COVID-19 pandemic, from January 9th to 24th, 2022, TOBUNKEN dispatched three staff experts responding to the request by APSARA for the first time after almost two years. We conducted the field survey and discussion on the points necessary for immediate consideration onsite including the East Gate under restoration as well as the parts of the central complex of the temple that are considered at risk.
The APSARA team have continued the restoration project of the East Gate started in 2019 by discussing the specific restoration direction online with us after April 2020. In January 2021, the reassembly work of the superstructure was completed up to the top. We checked the details onsite including the accuracies of the construction and the finishing details, which had not been well grasped remotely, and provided advice for improvement. Some retouching and additional works are planned based on the further discussion.
The central building complex of the temple requires immediate measures to secure visitors’ safety and prevent further damage to the ruins due to multiple risk factors including the collapse of unstable stone materials, aging of temporary timber reinforcements, and impacts by growing trees. Considering the given situation, we conducted a joint survey with the APSARA risk map team and discussed the main direction for countermeasures and the priority of temporary measures. We also recorded the current status of the towers by checking the upper part using a drone and creating 3D models from the photos taken.
In addition, the analysis of soil specimens taken in the previous archaeological survey at the front causeway was made with the assistance by Korea Cultural Heritage Foundation (KCHF), which also continues the restoration support in the Angkor archaeological site. In the APSARA Laboratory developed with Korea’s support, we conducted tests including grain size analysis and color measurement, which provided data related to the soil layer comprising the foundation of the causeway. We would like to express our gratitude to the generous support provided by KCHF.
We renewed our recognition of how important the onsite cooperative activities are, including interaction with the teams from different countries onsite and at research meetings. The mission also implemented the excavation survey of the outer enclosure and the survey on the stored sculptures from Ta Nei, which are reported separately.
The East Gate in the rainy season
The foundation of the outer enclosure and the land surface at Angkor Period unearthed
As part of the project mission from January 9th to 24th, 2022, we conducted an excavation survey of the outer enclosure remains of Ta Nei temple Under restoration of the East Gate implemented in cooperation with APSARA, the reassembly work has already been finished. However, due to the lower land surface than the surrounding area, it has been problematic in that the rain water accumulates around the gate in the rainy season. We assumed that this could hardly happen with the original setting when the temple was built, in which it was believed to have been equipped with some form of water drainage system. With this assumption, we conducted an excavation survey to understand the land surface level and terrain status at that time to plan a water drainage system around the East Gate area.
We conducted an excavation survey at the three points along the base remains of the wall that used to connect to the south and north sides of the gate (no information on the time and reason for removing the wall structure): its northeast corner and two locations where laterite blocks of the wall base are exposed up to the corner. The survey revealed that the land surface at these points in the Angkor period was about 30 centimeters below the current surface. This means that it was almost flat land without particular height difference from the surface around the East Gate. We did not find any remains such as drainage channels, so we consider that the drainage at that time depended on the natural drainage system including percolation.
The area to the north of the Gate is currently elevated, which prevents water evacuation. We will therefore remove the topsoil in that area and check if the rainwater can be discharged better. We plan to reorganize the surrounding area as well as the restoration of the temple buildings.
Damaged Dvarapala statue
Onsite survey
As part of the onsite survey mission from January 9th to 24th, 2022, the survey was conducted on the current location and status of the stone statues found in Ta Nei Temple and stored in other places. The French School of the Far East (L’Ecole française d’Extrême-Orient, EFEO) compiled the records of the discovery of the artifacts from different monument sites in Angkor. However, the systematic survey for the current status of these artifacts had not been conducted.
With the cooperation of the Angkor Conservation Office (ACO) under the Ministry of Culture and Fine Arts, we conducted a verification survey of the artifacts stored at that office against the records. There are a total of 30 plus artifacts from Ta Nei Temple on the inventory list created by the EFEO, among which, 16 items were identified at the storages of ACO this time. Most of the rest whose location remains unknown are small pieces such as hands or feet of divine statues. Among the massive statues of the gate guardian Dvarapala, which are about 2 meters high, three have lost their heads that were visible in the previous photographs. In addition, one of the Lokesvara (Avalokiteshvara Bodhisattva) statues was found to be heavily damaged. These damages are considered to be made by illegal diggings or destruction during the civil war period. The information from a French researcher onsite helped us to determine that at least two statues on the inventory, apart from the 16 items identified in the ACO, are currently stored in the National Museum of Cambodia in Phnom Penh.
We also found that a group of statues collected from the monument sites by ACO around in 1993 and 1994, when illegal diggings were most frequent, includes ones moved from Ta Nei Temple. We then identified seven Seated Buddha statues, seven Naga balustrades, and two Sinha statues. We will further investigate where they were originally located in the temple and where the rest of the artifacts are stored.
On the other hand, part of the head of a Lokesvara statue found inside the East Gate of Ta Nei during its dismantling in 2019 is stored in the Preah Norodom Sihanouk-Angkor Museum. We photographed it again for 3D model creation. The accompanying body parts have unfortunately not yet been found. It could still remain undiscovered on the site avoiding people’s eyes.
We plan to take the opportunity to conduct further surveys in the other facilities.
Study on the reinforcement measures for the foundation structure of the East Gate
The ICC Secretariat visited the restoration work site of the East Gate (courtesy of APSARA)
Tokyo National Research Institute for Cultural Properties provides continuous technical support to the Authority for the Protection and Management of Angkor and the Region of Siem Reap (APSARA) for the conservation and sustainable development of the ruins of Ta Nei Temple in Angkor, Cambodia. Last year, the restoration of the East Gate began under the Conservation and Sustainable Development Plan jointly developed by APSARA and the Institute. APSARA is responsible for securing the budget for materials and labors, as well as implementing the work. The Institute provides technical assistance on restoration methodologies and procedures, as well as cooperation in architectural and archaeological surveys before and during the work.
The possibility of our visiting Cambodia has all but disappeared after March this year, due to the global travel bans implemented to fight the COVID-19 pandemic. However, we cannot suspend the restoration work for our convenience, given that COVID-19 has not spread widely in Cambodia and the Cambodian counterpart has been continued regular site duties. From April, we have been benefiting from the advantages of Information & Communication Technology (ICT), actively utilizing interactive networking services with smartphones, besides normal e-mail messaging, to grasp real-time conditions at the site and hold online meetings as needed.
On the 21st of April, an online meeting was conducted with the East Gate restoration team of APSARA to share the result of the foundation’s geological testing during February and March and discuss restoration methods and structural reinforcement measures, based on the test result. Two of our collaborators, Professor KOSHIHARA Mikio (Structural Engineering) and Professor KUWANO Reiko (Geo-technical Engineering) from the Institute of Industrial Science, the University of Tokyo, joined the meeting. After an in-depth discussion from a scientific perspective, the participants finally agreed on a basic scheme for the restoration and reinforcement with an aim to balance heritage authenticity and structural safety. Under this basic scheme, online meetings were held in May and July to study about treating the foundation and superstructure, respectively. We had interactive discussions and shared ideas, plans, and other useful information, as well as the site’s latest condition, and decided that, at this stage, the concrete restoration/reinforcement method be considered the most appropriate one.
The Technical Session of the International Coordinating Committee for the Safeguarding and Development of the Historic Site of Angkor (ICC), organized at APSARA headquarters in June every year, was also postponed, and only the site visit by the ICC co-chairs and the secretariat was done this year. APSARA and the Institute jointly made the progress report and work plan of the project, including the activities mentioned above, and submitted it to the ICC secretariat prior to their site visit. We also held an online meeting with Professor MASUI Masaya of Kyoto University Graduate School, a member of the Ad Hoc Expert Group of the ICC, who supervised and advised us on our recent issues and the project’s work plan and exchanged information about latest information concerning international cooperation on Angkor.
In this way, we accidentally realized a potential of ICT in heritage conservation. Indeed, there is a natural limit to conservation efforts based on telecommunication and remote information sharing because the universal value of cultural heritage is in its object itself. We hope that the world returns to normal, after overcoming the COVID-19 pandemic, and the days of unrestricted international travel are back soon.
