Finland shares its Twin It! 3D for Europe’s culture story

Choosing the Twin- it! entry: a practical approach

To choose their Twin it! asset, the Finnish Ministry of Culture and Education reached out to the World Heritage 3D project at the Finnish Heritage Agency. The project is funded by the Ministry and aims to create the highest possible quality 3D digitisations of selected UNESCO World Heritage sites in Finland, as well as develop new infrastructure for storing and managing 3D cultural heritage assets. The project will also formulate and publish official guidelines for the Finnish heritage sector to optimise and standardise 3D digitisation workflows for the cultural built environment and 3D data management frameworks.

The World Heritage 3D project concentrated on two World Heritage Sites in Finland, Petäjävesi Old Church and Suomenlinna Fortress outside Helsinki. Both are popular tourist sites and threatened by gradual deterioration and natural catastrophes.

It was a lucky coincidence that the Twin it! campaign coincided with the Finnish Heritage Agency’s work to 3D digitise the Petäjävesi Old Church. In the last couple of years, the use of professional 3D digitisation has markedly increased at the Finnish Heritage Agency, and in the Finnish heritage sector more widely.The Petäjävesi Old Church project fitted the goals of Twin It!, and was always designed to publish 3D data openly with the public, although the digitisation was still a work in progress in Autumn 2023.

Watch the video below to see the final 3D model! 

The Petäjävesi Old Church

The Petäjävesi Old Church is situated in Petäjävesi, Central Finland, about 230 km north of Helsinki. It was built by land-owning peasants in 1763-1765, when Finland was still part of the Swedish Kingdom. The church, located by the banks of Lake Petäjävesi, was built by master builder Jaakko Klemetinpoika Leppänen. Some 60 years later, his grandson Erkki Jaakonpoika Leppänen supervised the addition of the iconic belltower.

The church is an impressive and representative example of Northern European wooden church architecture; its vaults, central cupola, and lay-out bear influences from European trends from Renaissance to Gothic, but everything is masterfully constructed in the best local log construction tradition. The church is almost entirely built from local pine wood.

The Petäjävesi Old Church has been inscribed on the World Heritage List since 1994, one of Finland’s seven UNESCO sites so far. It can be visited mostly in summertime. Thousands of tourists visit every year.

The 3D digitisation process

The Finnish Heritage Agency has experience and equipment in-house for small scale 3D-digitisation work which is concentrated around collection objects. Larger 3D digitisation projects are outsourced to external companies. These are usually procured by the Cultural Environment Department, for restoring and monitoring historical buildings.

One of the goals of the World Heritage 3D project was to create and preserve as high quality 3D data as possible, which could be used as the basis of reconstruction if needed. In order to operate safely and protect the site, and to determine what sort of 3D-data would best support the protection and preservation of the Church, it was important to thoroughly understand the building. Built heritage experts from both FHA and the Evangelical Lutheran Church of Finland were closely involved. We chose the Finnish data modelling company Tietoa Finland Oy to carry out the digitisation according to our plans and instructions. The final work plans were drawn after visiting the site in Petäjävesi together with FHA and Tietoa Finland staff.

The field work lasted about two weeks in September 2023. The Church was captured from inside and outside with the help of laser scanners, cameras, tachymeters and drones. As rewarding a subject as the Church turned out to be, it was by no means an easy one. There was very little light inside the foundations and roof structures; the complex geometry of criss-crossing wooden beams and bars made scanning sometimes painfully slow; and we had to use proper equipment to protect ourselves against the risk of viruses. The amount of final raw data and project files is massive – some 5 terabytes altogether - and over 7,000 photographs alone were taken.

Processing of the data was finished by the end of 2023. The cleaned, raw data and a mammoth-sized final, textured OBJ-model of the whole Church, were preserved in FHA archives. Optimised 3D-models that could be shared with audiences via the internet were published both on Finna.fi and Europeana.eu in early 2024. Publishing was done in cooperation with the Finnish National Library, who maintains the Finna-service, and is also our national aggregator for Europeana.

The Petäjävesi models were the first 3D-models from Finland ever to be published in Europeana.eu. This meant some new changes and tweaking for the Formula-service, which the National Library uses to transfer metadata and digital objects to Europeana.eu.

We produced a short documentary about the progress of the 3D digitisation project - watch it below!

Visions for 3D in the future

We at the Finnish Heritage Agency foresee clear benefits of 3D digitisation of Finland’s cultural heritage. By using 3D technologies, we can preserve our cultural heritage better than ever before, even though it naturally can never replace the original. The use of 3D-digitisation should be especially ramped up to document more, why not all, Finnish built heritage at risk.

In the case of the Petäjävesi Project, we managed to capture nearly the whole building in 3D with the accuracy and precision of millimetres. Datasets like these are an unparalleled tool for research, protection and monitoring in conservation efforts, and high quality measurements can be accessed digitally even from distance.

Making high quality 3D ‘digital twins’ is time consuming and expensive, so thorough planning and prioritising are paramount. Long-term preservation and findability of 3D data is also crucial, and we need to invest in efficient new infrastructure and expertise in IT and collection management. In the future, we also hope to see more collaboration, participation and knowledge exchange between the cultural heritage and private sectors.

The real winners of 3D digitisation are of course all of us. Through new 3D-technologies, we can create fertile grounds for creativity and business to thrive and make our heritage more easily accessible and available to everyone.