On December 9 the project “Saint Sophia’s Inscriptions” was presented. It’s a digital documentation of inscriptions in the Saint Sophia Cathedral in Kyiv. Such a research infrastructure allows scholars and the public to explore the inscriptions of Sophia Cathedral, the oldest of which are from the first half of the 11th century.

This project is the result of a close collaboration between the National Conservation Area “St. Sophia of Kyiv”, the National Museum of the History of Ukraine (MIST) and the University of Gothenburg, Sweden. The team should document the inscriptions using various digital technologies and publish the data through an online portal.

There are more than 7,000 inscriptions carved into the walls of St. Sophia Cathedral. They span over a thousand years and follow different languages and writing systems. These inscriptions are a source of knowledge about human cultural history, language and writing, migration, trade, cultural exchange and cultural diversity in Europe. And such an important primary source for various disciplines is acutely threatened by Russia’s war against Ukraine. The project therefore aims to help preserve this cultural heritage for future research.

The project is led by Gunnar Almevik, professor at the Department of Conservation at the University of Gothenburg (Sweden). His team has extensive experience in digitisation. For example, they did it for the first Swedish Antarctic expedition. Gunnar Almevik told us about the challenges of digitising Saint Sophia’s inscriptions, the development of this initiative and some trends in the field.

Gunnar Almevik in Saint Sophia Cathedral. Photo by Jonathan Westin

“The graffiti bring a continuous dialogue and transformation”

 How did the project begin? As far as I know, it started with enthusiasm. 

The need to engage in the documentation and preservation of the graffiti in Saint Sophia Cathedral was of course urged by Russia’s aggressive warfare and discussed within the National Conservation Area “St. Sophia of Kyiv” and MIST. 

This first came to me and my university colleague Jonathan Westin as a phone call from the Swedish National Heritage Board, who discussed actions and solutions with Kyiv. Jonathan and I have done a lot of work on digitisation and risk assessment of endangered cultural heritage, including historic cultural remains threatened by climate change in Antarctica. That’s why they called us. We have equipment, experience and skills. And yes, we are mainly following the heart and spirit of what we are doing, but of course with a constant focus on science. 

From there we formulated a project together and raised the funds to get started. We received grants from the Swedish research council FORMAS, the Royal Swedish Academy of Letters, History and Antiquities and the Swedish National Heritage Board. Of course, a lot of work is put in, not least from staff at the National Conservation Area “St. Sophia of Kyiv” and also MIST. 

Work in Saint Sophia of Kyiv began in January 2024. What was your first impression of the cathedral? 

Wow, it's a time capsule. It’s a beautiful space and it gives you comfort and confidence to be there. I also noticed that even though the walls are covered with graffiti, it’s very respectful. The monument is also a document and the graffiti brings a constant dialogue and transformation. It somehow challenges the rigidity of contemporary heritage conservation. 

Vjatjeslav Kornienko, research manager at the National Conservation Area “St. Sophia of Kyiv”, conducted the inscription guiding tour for the project team. Photo by Gunnar Almevik

“Working with Saint Sophia’s graffiti, we experimented a lot”

There are more than 7,000 graffiti on the walls of Saint Sophia. How long did it take to digitise them? What was the most difficult part of the work? Do you remember which inscription or inscriptions were the most difficult to digitise?   

Ah, we are far from finished. I think we’re up to about 25 % of the surfaces, but probably more of the inscriptions as we’ve concentrated on the murals with a lot of information. It has taken time to choose the techniques and develop the working methods. The most challenging part of the process is data management and quality assessment. It’s one thing to collect the data, but to evaluate it we need to transfer and process it, so the feedback loops are difficult, also because of the distance between the members of the group. 

We’re trying to get the same high level of quality, in particular with dense and important inscriptions. But technically it’s difficult with curved surfaces and places that are high off the ground. We used a mural of Saint Onuphrius as a test and it has over 300 inscriptions, many of which overlap. 

A 16–17th-century inscription on the wall of St. Sophia Cathedral in Armenian: “Unfortunately, my hand will be gone, but the work (written by me) will remain firmly here. Whoever reads what is written will say: ‘Lord, have mercy on this slave.’ Amen.” Photo by Fedir Androshchuk

What technologies did you use? Did you experiment with them during this work? 

We experimented a lot. Again, we had to balance quality with cost and time. In the end, we used laser scanning of the entire interior. But in order to achieve quality at the scale of the inscriptions in a feasible way, we worked mainly with image-based techniques such as photogrammetry for 3D models and reflectance transformation imaging (RTI. – Ed.), which is a kind of digital rake light. 

Sergii Trofymchuk, architect at the National Conservation Area “St. Sophia of Kyiv,” taking photos for work in 3D photogrammetry. It requires about 1000 images per square meter to get a high resolution model. Photo by Gunnar Almevik

What is the next stage of digitisation after the images have been taken?

We take the photographs and process them in different software to get 3D models, the rake light or relight models and high resolution orthographic (measurable) photographs. We also process the 3D models to improve the topographical features, to see small details in the inscriptions.

In the future, it would be interesting to use other heritage science methods, for example to see any underpainting, to determine pigments and binders without destructive analysis, and possibly also to examine surfaces where the 17th-сentury plaster covers any original murals. 

“The portal and visualisation techniques help with interpretations”

For many people, digitisation means taking photographs. But in this way we only get stocks of “dumb” photos without any information about them. What can users find out about the inscriptions on the website? 

The portal I would say will be a very good tool for both researchers who want to interpret the inscriptions, but also for the common public to see the church and zoom in on the details and inscriptions wherever they want. 

When you are on site you know that it’s very difficult to see the inscriptions. You see that they are there but to read them and to distinguish the forms is hard. The technology enhances the readability. In the portal we also have tools to measure and to transcribe the inscriptions. 

The project team is working with photogrammetry. Photo by Jonathan Westin

You said earlier that this project can help to gain new knowledge about the inscriptions of Saint Sophia, as they will be available to researchers all over the world through the web platform. What information about these graffiti is a white spot now?

We are certain of that there are unknown unknowns: inscriptions that have not yet been identified. The portal and visualisation techniques also help with interpretations. There are many inscriptions that are identified but not translated. There might also be misinterpretations or contesting interpretations. I think that there are many contextual questions that could be investigated. We may also learn about writing styles, spellings, what people wrote where in the church, patterns from an author, relations between text and images, relation between the social class or gender of the authors and the locations of inscriptions and style of writing, attribution of the different images, dating of styles. And many other possible research questions.

Unfortunately, all heritage objects in Ukraine are threatened by the war. I know that the continuation of the project with St. Sophia will help to develop digitisation in the country. Could you tell me more about this initiative? 

Yes! DIGICURE (comes from the phrase (“Digital Cultural Resilience and Protection.” – Ed.)). The Swedish Institute has supported a two-year training project in digital contingency planning. Jonathan Westin and the Gothenburg University’s research infrastructure for digital humanities have the lead, and collaborate with MIST and the National Conservation Area “St. Sophia of Kyiv”.

With this project we aim to use the competence developed and equipment acquired so far at and expand the group of the “St. Sophia of Kyiv” and MIST with professional stakeholders. First, we will teach the trainers in a group of about 20 persons. We will connect the group to professional organisations and institutes in Europe concerning cultural heritage, risk assessment and digitisation. Then we will offer training for regional and local professionals in the Ukrainian heritage sector to be able to perform documentation and also share knowledge with colleagues and local networks.

“The documentation of the impact of climate change on cultural heritage assets is also a way to stress the urgency for action”

Your team’s previous digitisation project was linked to the first Swedish Antarctic Expedition. Perhaps it’s a completely different experience compared to the Saint Sophia inscriptions. What was the most challenging part of working in such extreme climatic conditions? Why is digitisation important for such objects?

Well, it’s cold down there. The limited transportation and communication, and the unpredictable weather also make it a bit dangerous. We stayed in different locations following in the footsteps of the first Swedish Antarctic expedition in 1901–1903. It was a research exhibition and they left remains of a research station and stone huts.

Most people don’t go there. Very few people can go there. This is a whole continent as a nature reserve. Therefore, it’s important to make these environments digitally accessible to people. In the global poles, the speed of transformation due to climate change is really fast and visible. The documentation and dissemination of the impact of climate change on cultural heritage assets is also a way to stress the urgency for action. 

The basecamp on Snow Hill Island. The expeditioners from 1901 built the wooden research station there. Now it is an Antarctic heritage.Photo by Jonathan Westin

Hope Bay where one group of expeditioners where stranded and had to in hibernate the winter. Photo by Jonathan Westin

How do you think digitisation technologies will develop? How can artificial intelligence help in this area? 

Yes, certainly in many ways. It is already a realistic opportunity to use AI in the portal to analyse data. It could for instance be used to detect new inscriptions in the 3D models or identify writing styles and individual signs among the 7,000 inscriptions.

Your PhD thesis was dedicated to the building as a source of knowledge. What makes this source unique, compared to others, such as documents etc.?

Buildings are present in our daily life. They immerse us and act upon us. We are all used to buildings and know our ways around and how to interpret its coding at least at a basic level. The diversity of expressions and different ways of structuring spaces, consume materials and compose constructions provide let us all reflect on why they are built like this, what was the meaning and what life histories and societies they were involved in during history.

Do you have a professional dream to digitise a specific cultural heritage object?

Well, I would love to come up in the attic and the crypt of Saint Sophia (one of the highest and underground parts of the church. – Ed.) and share the experience through a digital model.

Mariia Prokopenko

The first image made by Anastasiia Ptashynska