Not Many Know, Borobudur Temple Was Once Coated in Concrete

Few people are aware that Borobudur Temple has a layer of concrete within its structure, even though this magnificent building holds the status of a cultural heritage site. Compiled from the Museum and Cultural Heritage of Borobudur, the decision to pour concrete over parts of the temple was taken as a preservation measure following lengthy discussions among international experts. In the late 1960s, Borobudur faced serious threats from continuous water seepage that was damaging the stone structure and the weakening base soil. If not addressed promptly, the damage could worsen and even threaten the building’s stability. During the study process at that time, various restoration options were considered, including extreme methods. To find the best solution, at UNESCO’s initiative, international experts gathered in Yogyakarta on 18-19 January 1971. That decision then became the basis for the implementation of the Borobudur Restoration II, a massive restoration project that lasted nearly a decade. During that restoration, concrete was indeed installed in the inner parts of the temple’s structure. However, this material was not used to replace the temple’s original stone, but rather as a hidden reinforcement system to keep the structure sturdy without changing its original appearance. There were several main elements installed. First, concrete slabs or plates installed around the temple’s corridors at each level. These plates are hidden under the stone floor and function to distribute loads evenly, strengthen weak structural points, and resist water pressure. Their function is to channel rainwater out from the temple’s body and prevent seepage, which has been the main cause of damage. Third, vertical and horizontal water channels connecting the temple’s levels.