Why Digitise the Past in 3D?

The digitisation of cultural heritage has traditionally focused on capturing geometry, physical properties, and appearance through advanced, smart 3D documentation technologies. Yet, can geometry alone truly represent our past? Is geometry representing a building, or a monument, is it representing an object or an artefact? Cultural heritage is much more than its physical form: it embodies knowledge, memories, stories, traditions, human experiences, values, and identities passed down through generations over the time.

This contribution explores the transition from geometry-centred digitisation towards a holistic, knowledge-driven approach integrating tangible and intangible heritage. It emphasises the importance of applying the FAIR principles (Findable, Accessible, Interoperable and Reusable) and the CARE principles (Collective Benefit, Authority to Control, Responsibility and Ethics) throughout data acquisition and management, ensuring that digital heritage is scientifically reusable, ethically responsible, and respectful of the rights and values of communities.

Furthermore, Paradata, documenting who did, what, when, where, how, why, and under which conditions data are acquired and processed/modelled, is highlighted as a fundamental Certificate of Quality in Data Acquisition, supporting transparency, traceability, reproducibility, and the validation of 3D documentation over the time. By combining these principles with artificial intelligence, community narratives and semantic knowledge the emerging MemoryTwin paradigm extends the Digital Twin beyond geometry to capture the histories, experiences, meanings, and identities associated with heritage assets.

Therefore, digitising the past should not merely preserve what heritage looks like, but also safeguard what it represents and means: preserving the authentic DNA of human memory for current and future generations.

This presentation introduces the first implementation of a Memory Twin in Malta, developed through ongoing research and work on the Malta Dockyard Collection. This collection brings together industrial objects, shipbuilding tools, machinery, technical drawings, photographs, archival records, and personal testimonies connected with one of Malta’s most significant maritime and industrial landscapes. It provides a concrete case in which digitisation must move beyond the production of 3D models or visual records, since the physical assets cannot be separated from the knowledge, skills, working practices, social histories, oral memories, and identities of the Dockyard communities that produced, used, and remembered them.

By applying the Memory Twin framework to this case, the 3D model becomes the beginning of a wider knowledge system rather than the end of the digitisation process. A digitised tool, engine component, vessel model, drawing, or photograph can act as an anchor through which tangible and intangible heritage are connected to places, processes, people, terminology, narratives, values, and community memory. This Maltese implementation demonstrates how digitisation can create meaningful relations between collection items, the Dockyard landscape, archival evidence, and lived experience, transforming digital records into a living and traceable framework for understanding cultural heritage.

In the digitisation discourse, there is a recurring tendency to frame digitisation as a one-time commitment, and even when a long-term commitment to maintaining digital information is acknowledged, it is conceived primarily as a technical task rather than an undertaking pertaining to the digitised content. Combined with the parallel tendencies of assuming that the opportunities of and reasons for digitisation are similar across organisations and audiences, and of omitting that their underpinning rationales tend to be much more diverse and nuanced, digitisation risks to stand out as a complicated and costly but manageable task.

Considering the diversity of rationales and audiences and their change in time, what is too often neglected is that the most successful digital collections and archives are those that are used and updated regularly. The aim of this presentation is to discuss using examples from digitisation projects how digitisation should be framed as a perpetual commitment of not only ensuring the technical sustainability of digitised assets but also to their use, enrichment and updating to ensure their future relevance and the return of investment of the on-going and planned massive digitisation efforts.

Books have a double life. They are carriers of information, preserving language, images, and ideas, but they are also physical objects whose materials, construction, alterations, and traces of use provide evidence of their production and history. Digital representations have traditionally privileged the former, treating the book primarily as a sequence of pages to be photographed, transcribed, indexed, and searched. Yet the material object contains another body of evidence that cannot be recovered from its textual content alone.

This talk examines two complementary paths towards the construction of digital twins of historical books. The semiotic path concerns the recovery and interpretation of textual and visual content through document analysis, optical character recognition, semantic annotation, and knowledge extraction. The material path concerns the documentation and interpretation of the physical artefact through imaging, geometric reconstruction, material characterisation, and the study of bindings, construction techniques, condition, and traces of intervention. Each path produces different observations, representations, and scholarly claims about the same historical object.

A central challenge is not merely to combine these representations, but to preserve the evidence and reasoning through which they were produced. Here, paradata becomes a fundamental component of the digital twin. Beyond recording the provenance of digital assets, paradata documents the processes of observation, computation, interpretation, and validation: which methods were applied, under what assumptions and parameters, what transformations were performed, where uncertainty remains, and which conclusions depend on human judgement. It makes explicit the distinction between what was observed, what was computed, and what was inferred.

Drawing on the work of the Horizon Europe ARXIVE project, the talk discusses how documentary parsing, material evidence, semantic interoperability, and paradata can contribute to evidence-preserving digital twins. The proposed perspective treats the digital twin not as a definitive virtual replica, but as an evolving scholarly representation in which multiple forms of evidence coexist, interpretations remain traceable, and new observations can revise existing knowledge.

The purpose of digitising heritage in 3D should guide every decision about how it is recorded. For buildings, monuments, ruins and landscapes, a digital record can support understanding, conservation, repair, adaptation, monitoring and recovery after damage. Its lasting value depends on whether future users can trust the measurements, understand the evidence and apply it to new questions.

Drawing on practical experience in heritage geospatial surveying, this presentation explores how these objectives translate into proportionate requirements for capture and documentation. Examples from conservation practice will illustrate the importance of establishing what information is needed, the accuracy and completeness required, and how surveys undertaken at different times can be reliably compared.

Historic England's Geospatial Survey Specifications for Cultural Heritage (HEAG317) provides a reference for connecting these purposes with established survey methods, spatial control and verification. The presentation also considers how metadata and paradata preserve the context, decisions and limitations needed to interpret and reuse the resulting information.

The central proposition is that 3D digitisation is an act of custodianship. Clear objectives, appropriate professional expertise and consistent application of existing guidance help ensure that the records created today remain useful evidence for those who will care for our heritage tomorrow.

The life and sometimes destruction of our historical monuments, community treasures, and heritage - tangible and intangible materials - raises questions about preserving our cultural memories and collective meaning in various creative form, including any or all of the advanced digital capabilities available to us. This preservation is in part a commitment to make what is passing, what comes from the material and malleable and mortal world, to be able to be conveyed in some form and maintained well into the future - potentially for thousands of years. This has long been a means of preserving enough of a society to provide a kind of immortality, and a means of connecting peoples across eons.

With the growing importance of IIIF standardization for the world's most sharable and sustainable digital collections, 3D data adds extensive additions to the ability to preserve our past and presents a future with greater depths and dimensions of suitable narratives and factual fidelity. The newly launched (June 2026) IIIF Presentation API 4.0 includes the standards for interoperable 3D content, expanding the potential for all IIIF-based collections. This presentation will review some of the new capabilities, to incorporate great examples from multiple 3D collections, for instance to create digital dioramas or recreate existing physical scenes. Tools such as for AI-enabled model, metadata and scene generation will be shared, along with examples of incorporating 2D and A/V with 3D data, including for scene construction considerations, and for more inclusive and sustainable virtual worlds.

In addition this presentation will provide an overview with use cases, some available demos of combining and extending these capabilities to help develop the requirements for memory twins, including the potential to extend the IIIF concept of a manifest - a standardised structuring of a JSON file - to potentially parameterise the essential PARADATA which would be needed to make memory twins interoperable.