Restorers to rebuild first bone pyramid from famous medieval ossuary

A team of experts have started to reconstruct one of the four bone pyramids from the famous 14th century ossuary near the town of Kutná Hora. If everything goes according to plan, the first bell-shaped mound, made of hundreds of thousands of bones and skulls, should return to the ossuary by the end of the year.

The medieval ossuary in Sedlec is one of the most visited historical attractions in the Czech Republic, drawing hundreds of thousands of visitors every year.

The former medieval chapel, located in the basement of a Roman Catholic Church, houses the bones of an estimated 40,000 to 70,000 people who died during the mid-14th century plague and in the subsequent Hussite Wars, assembled in all sorts of formations, including a chandelier and a coat of arms of the local aristocratic rulers.

Photo: Josef Vostárek,  ČTK

Since 2014, the chapel has been undergoing an extensive renovation, which is now drawing to a close. However, the restorers are still facing a major challenge: to reassemble the bones into the original shape of a pyramid. Architect Vít Mlázovský is in charge of the project:

“Over the years, the pyramid has sagged due to moisture and the associated mould infestation, which destroyed mainly the bottom layers.

“We had to figure out how to prevent its further deterioration. The first pyramid is sort of a pilot project, where we want to try out the different procedures.”

Photo: Josef Vostárek,  ČTK

The original pyramid contained around 12 cubic metres of bones, which had to be dismantled, cleaned and preserved, says restorer Tomáš Král:

“We know from the original documentation that, already in the 16th century, the remains from the graves went through a special treatment.

“Lime milk solution was used for the initial removal of dirt, and it also served as a disinfectant. Only after the bones were dried were they placed in the interior of the chapel.”

Photo: Josef Vostárek,  ČTK

To treat the bones and skulls, the restorers used the same method as their predecessors. While they wanted to preserve as much historical material as possible, some of the bones could no longer be used due to the effects of moisture and time.

From the outside, the pyramid will look exactly as it did some 500 years ago. However, the new mound will be hollow, with the bones assembled on a supporting wooden construction, explains Mr. Král:

“After the installation of the supporting wooden structure, the fitting of the original restored wooden elements will take place, and only then we will install the bones.

“We want to finish the pyramid by the end of this year, but it can tricky, since we are still learning how to assemble the bone links. So it is possible that the whole process will be delayed.”

The reconstruction of one single bone pyramid cost around 20 million crowns and it is not yet clear when the others will be rebuilt. The local parish, which is the main investor in the reconstruction, draws money for the repairs only from entrance fees.

Authors: Ruth Fraňková , Ondřej Ševčík
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