3D Data Capture of Nagasaki Prefecture's "Gunkanjima"! HERITAGE DATABANK Expands Possibilities for World Heritage Preservation and Utilization

Dentsu Inc. has launched the "HERITAGE DATABANK" project. This initiative preserves precious natural and cultural assets, including World Heritage sites, by converting them into 3D data. By collaborating with various companies and organizations to utilize this data, the project aims to contribute back to the conservation efforts of these assets. It is an endeavor to expand the social value and utilization potential of global assets through digital archiving technology, thereby ensuring their continued preservation.

As the project's first initiative, the World Heritage site Hashima (Battleship Island) in Nagasaki City, Nagasaki Prefecture, has been converted into 3D data. In this article, members of the HERITAGE DATABANK team leading the project explain the background and significance of its launch, future developments balancing preservation and utilization, and this case study.

<Table of Contents>

▼Addressing World Heritage Conservation Challenges with Technology and Creativity
A New Approach

▼Collaborating with Nagasaki City to Create Complete 3D Data of the "90% Off-Limits" World Heritage Site, Gunkanjima

▼Beyond Digitization: Hosting the "Shibuya Gunkanjima Exhibition" to Explore Archive Data Potential

▼Realizing New Applications for Gunkanjima Data: A Model Case Balancing Preservation and Utilization

Addressing conservation challenges facing World Heritage sites with technology and creativity

World Heritage sites and other precious assets face significant challenges in continuously "preserving" their magnificent forms. Various reasons exist, including natural disasters, armed conflicts, and destruction or wear caused by overtourism. The reality is that funds for preservation and maintenance are also insufficient.

Amidst this, digital archiving is gaining attention. This approach involves digitizing valuable assets through 3D scanning and preserving them digitally. While some municipalities have already started initiatives, implementation requires substantial costs comparable to physical conservation.

Dentsu Inc.'s "HERITAGE DATABANK" project addresses this by combining digital archiving with creative design to build an ecosystem that achieves both "conservation" and "monetization." Beyond digitally preserving valuable assets as 3D data, the project aims to utilize this 3D data for tourism, entertainment/games, education, research, and other applications, thereby monetizing conservation activities.

Project member Konishi conducted research on the deterioration of Gunkanjima during his university days, which made him keenly aware of the challenges in preserving World Heritage sites. This experience sparked the project's inception—the idea that preservation shouldn't just be about spending budgets, but about finding ways to create new value through preservation.

Working with Nagasaki City, we fully 3D-mapped the World Heritage site Gunkanjima, where 90% is off-limits.

The project's first phase focused on Nagasaki City's Gunkanjima, a site considered difficult to preserve due to geographical and technical constraints. Registered as part of the Meiji Industrial Revolution Sites in Japan, its dense cluster of buildings creates a distinctive warship-like landscape, making it a popular destination for tourists both domestically and internationally.

However, access is not easy. Although there is a partial landing tour route, days when landing is impossible due to rough seas or other maritime conditions frequently occur. Furthermore, the buildings are deteriorating at an ongoing rate, resulting in 90% of the island being off-limits.

Consequently, landing permits for restricted areas are typically granted only for research or academic purposes. Even when permitted, stays are usually limited to one or two days. Amidst these circumstances, HERITAGE DATABANK, as part of its digital archiving and conservation efforts, successfully conducted a large-scale 3D scan of Gunkanjima with the full cooperation of Nagasaki City.

The technology used for the digital archive is called "photogrammetry." This method involves capturing images of the subject from various angles, then analyzing and integrating these digital images to create a three-dimensional 3DCG model.

Working alongside one of the world's leading 3D scanning teams, we spent about two weeks on Gunkanjima, where 90% of the island is off-limits. Guided by Nagasaki City officials, we documented every corner of the island, from buildings to debris, avoiding dangerous areas. In some safe buildings, we even entered interiors, scanning residences, school classrooms, gymnasiums, and other spaces that evoke life as it was then.

City officials shared the realities of preserving Gunkanjima while showing us the actual sites: "This wall was still standing just a week ago," "The top floor of this building collapsed six months ago," and "It's incredibly difficult to protect everything."

Not only did we observe the deteriorating buildings of Gunkanjima from afar, but we also gained access to them and heard firsthand accounts from city officials. This experience deepened our understanding of this project's mission and necessity.

We held the "Shibuya Gunkanjima Exhibition," challenging the potential of archive data beyond mere digitization!

In January 2024, marking 50 years since Gunkanjima's closure, we held the "Shibuya Gunkanjima Exhibition," a special exhibition utilizing Gunkanjima's archive data. By combining digital archives with creativity, we elevated the data into diverse expressions, showcasing the new potential of archive data from Shibuya, the heart of culture.

The Shibuya Gunkanjima Exhibition featured three forms of expression.

"Virtual Gunkanjima Photo Exhibition"
The highlight was the world's first virtual Battleship Island photos, captured by photographer Takeshi Sato.

Sato, who has appeared on programs like TBS's "Crazy Journey," photographs "strange things" around the world from a natural history and aesthetic perspective. He is the author of the photo book series "Strange World Heritage."

Sato photographed the 2018 photo book "THE ISLAND Gunkanjima." He explained that while shooting, he often encountered compositions he wanted to capture—specific angles or locations—but had to abandon them due to densely packed buildings or the inherent danger of collapse.

This time, by importing 3D data of the entire Battleship Island into a virtual photography system developed by Think & Craft, he was able to capture angles made possible only by virtual techniques—perspectives difficult to achieve in the actual shooting environment. Furthermore, by simulating on the system, he could freely set the time of day and weather, recreating Battleship Island at dawn or night—times when landing is normally impossible—and challenged himself to create photographic expressions impossible in the real world.

Sato refers to this technique as "imaging."

After the shoot, Sato commented on this new experience: "I've landed on Gunkanjima several times before, but this time I 'landed' in a completely new way. The light spilling through the gaps of the majestic, now-ruined buildings, the unique shadows and light patterns on the island shifting with the passage of time. As I stared at the screen and 'walked' around the island, memories of the island flashed back, immersing me in the realistic scene before my eyes. It was nostalgic, yet simultaneously a new, unknown experience."

"Virtual Gunkanjima Dissection Exhibition"
Gunkanjima, which boasted the world's highest population density in the 1960s, features an extremely high concentration of buildings.

Leveraging the advantages of 3D data, we extracted and displayed each individual historical building still existing on Gunkanjima, achieving an unprecedented representation of its structures. This includes Japan's oldest reinforced concrete apartment building and documents the deteriorating "present" of Gunkanjima.

"Virtual Battleship Island Landing Exhibition"
This project allows the general public to experience the virtual Battleship Island exploration content actually used by photographer Kenji Sato during his shoot.

The controls feel similar to operating a drone. Using a controller, visitors can move their position and viewpoint, and utilize camera functions including zoom, exposure, white balance, and shutter. This allows them to virtually step into Gunkanjima's restricted areas, record their own unique Gunkanjima through virtual photos, and even print them.

For this Shibuya Battleship Island exhibition, we had no prior advertising and were uncertain how many people would attend. Ultimately, over 1,000 visitors came over five days, and the event was covered by multiple media outlets.

What surprised us was that among the visitors, there was not only a "preview" need, such as "I'm going to Gunkanjima soon," but also a "post-visit" need, like "I went to Gunkanjima but now want to see the restricted areas too."

Visitors came with diverse purposes: fans of Mr. Sato, of course, but also those interested in technologies like 3D scanning, photogrammetry, Web3, and XR; those considering applications for creative production like virtual location shooting and scouting; and representatives from local governments and World Heritage management. This reaffirmed the potential of this field.

Furthermore, Nagasaki Mayor Shiro Suzuki attended and expressed his support for the project, calling it "a meaningful initiative to preserve the value of Gunkanjima for the future using digital technology."

Following the Shibuya Gunkanjima Exhibition, Nagasaki City hosted touring exhibitions at the Gunkanjima Museum and Glover Garden, receiving positive feedback from the local community and Nagasaki Prefecture. We too felt the significance of this project, making it an invaluable experience.

New applications for Gunkanjima data have also been realized. A model case where preservation and utilization coexist

Currently, we are advancing initiatives with various companies to utilize the archived data as content. At the Battleship Island Digital Museum in Nagasaki City, the data was utilized for 3D images within the newly established 3D theater.

It is also being utilized in the joint project "Metaverse Production" undertaken by Tohokushinsha Film Corporation, Dentsu Creative X, Dentsu Creative Cube, Hibino, and Omnibus Japan.

■ Related articles on Metaverse Production
" The Future of Video Production × Sustainability, Shaped by Technology "

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"Metaverse Production" utilizes in-camera VFX to display 3D data on rear LED displays, enabling filming with immersive expressions that make it feel like you're actually there without needing to visit the location. This approach is expected to reduce greenhouse gas emissions and streamline processes in video production.

This time, we utilized the 3D data of Gunkanjima we produced as background assets displayed on LED screens ( see release here ), advancing collaboration within the Dentsu Group.

We have already secured filming permissions from multiple World Heritage sites and tourist facilities, and have received inquiries from various local governments. We are also advancing collaborations with companies in the travel/tourism, XR/Web3, and gaming/entertainment sectors.

This project is still in its early stages.

Using the Battleship Island case as a model, we aim to expand this solution—which enables simultaneous digital archival preservation and increased awareness/tourism attraction through data utilization—to other World Heritage sites, cultural properties, and global assets.

【HERITAGE DATABANK】Members】
Dentsu Inc. BXCC・Kei Konishi / Dentsu Inc. 2BX Bureau・Yohei Ieizumi / 1CRP Bureau・Tomoya Morohoshi / 1CRP Bureau・Taisuke Yoshimori

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