Professor Yoshiyuki Yamana Visits Bokor Church: Valuable Academic Support for Heritage Conservation

On Sunday, 18 October 2026, Professor Yoshiyuki Yamana of the Department of Architecture, Faculty of Science and Technology at Tokyo University of Science, visited the historic Church of Mount Bokor.

He arrived the previous day, 17 October, via Sihanoukville Airport and spent the night at the Villa des Manguiers, the home of our friend Pierre-Yves de Keister, overlooking the beautiful river of Kampot. Early Sunday morning, under a beautiful late-monsoon sky, we ascended Mount Bokor. We first met Professor Yamana at the Archives of our Society in early September. His gracious assistance, together with the support of Mr Ivan Tizianel of the ASMA architecture firm, provides precious expertise on the use of reinforced concrete, lime plasters mixed with local Kampot shells, and the construction of the barrel vault in the 1920s.

Their presence compensates for the absence of official historic-monument status and offers essential scientific guidance.

Professor Yamana was absolutely fascinated by the Bokor church. He has written a letter of recommendation to the Sumitomo Foundation in Japan, highlighting the historical and academic value of the church and its monolithic reinforced-concrete barrel vault (approximately 150 mm thick, with a span of about 7.7 m). This vault, cast in the mid-1920s, is one of the earliest examples of a curved reinforced-concrete roof in the religious architecture of Indochina, contemporary with the pioneering work of Auguste Perret. The letter supports our efforts to raise funds for restoration.

On Sunday afternoon we returned to Sihanoukville, where Professor Yamana appreciated the restoration of Saint Michael’s Church. This masterpiece of New Khmer Architecture was made possible by the collaboration between Father Ahadoberry of the Missions Étrangères de Paris and the architect Vann Molyvann. The 2025 restoration, supported by Aid to the Church in Need and the Missions Étrangères, has revitalised this living place of prayer for a still very active community.

Monday morning was devoted to exploring other sites from the Sangkum era in Sihanoukville, including the brewery and the local branch of the National Bank of Cambodia, restored by the ASMA firm. Professor Yamana praised the excellence of these restorations.

Before boarding his return flight from Sihanoukville Airport, Professor Yamana collected samples of stone, cement and lime from the Bokor church for laboratory analysis in Japan. He assured us of his support and of his firm intention to return at the end of December to monitor the progress of the works and to encourage a restoration carried out to the highest standards.