From trowel to AI: open source-supported reconstruction of a Bronze Age fortification

S2: Archaeology, Open Science & the Digital Humanities | Standard presentation
  • Thomas Simeth
  • Carola Metzner-Nebelsick
  • Louis Nebelsick

The presentation shows open source methods to investigate, analyze and reconstruct the Bronze Age fortification at Stätteberg near the Bavarian Danube. The entire workflow from digital prospection, documentation of the excavation, reconstruction of the wall, material quantities and labor calculations, to the creation of vivid reconstructions and atmospheric illustrations using 3D software and AI, will be presented.

It starts with digital prospection using freely available Lidar data, which can be accessed in Bavaria via the “Bayernatlas”. This provided an overview of the fortification (nearly 90 hectares) and identified suitable sites for archaeological excavation. In addition, the data can be analyzed in QGIS (viewshed analysis, slope analysis, etc.) and thus considerations can be made about the transport geography and strategic location of the hillfort.

The three subsequent excavation campaigns were documented in detail with the help of photogrammetry (isometric imaging and Structure from Motion). The focus of the research here was on the “cyclopean” stone walls, which in their collapsed state are still preserved today up to two meters high.

The resulting 3D models were used to analyze the stratigraphy of the wall profiles and to measure the volumes of the collapsed layers. Thus, in the 3D software, the corresponding volumes were virtually put back onto the still existing wall remains and an approximate reconstruction of the original height and structure of the wall were created.

On the basis of these collected data, it was now also possible to make calculations on the quantities of material formerly required for the construction of the entire wall, which in turn were the basis for considerations on the labor required for the construction of the wall.

Since the 3D models of the excavation area also included fully exposed parts of the wall facade, the wall, together with the gathered information, could be virtually raised again to its former height which led to the creation of a vivid 3D reconstruction. This 3D model could then be used for informative graphics on the construction method as well as for atmospheric illustrations.

Since it is very time consuming and difficult to edit the rendering of the reconstruction to create an atmospheric image (lighting, background, vegetation, composition, etc.), an attempt was made to simplify this step using open source AI image generation (stable diffusion). For this purpose, the AI was trained specifically on the appearance of the Bronze Age wall and its surroundings. This allows the output of any number of images of the wall in different styles, situations, saesons and moods, which can then be used as mood images for publications, exhibitions and lectures.

Using the example of the Bronze Age fortification on the Stätteberg, this lecture will show that the use of open source software can be applied in all steps of the research of such a site and provides vivid results that are exciting for the general public.