Geometric Authenticity in the Reconstruction of Architectural Heritage: A Methodological Approach

The reconstruction of architectural heritage destroyed by armed conflict poses significant methodological and ethical challenges, particularly with regard to ensuring geometric authenticity. This paper presents a comprehensive, non-destructive methodology for the quantitative assessment of geometric accuracy in reconstructed heritage structures, using the Old Bridge in Mostar, Bosnia and Herzegovina, as a representative case study. Destroyed in 1993 and reconstructed in 2004, the bridge provides a rare opportunity to compare a rebuilt monument with extensive pre-destruction documentation. The research integrates high-precision geodetic measurements with archival photogrammetric drawings to analyze positional deviations between the reconstructed structure and its original geometry. Several transformation models for georeferencing historical drawings are evaluated, demonstrating the superiority of locally adaptive approaches in minimizing systematic distortions. The results indicate a high overall level of geometric conformity, with average deviations on the order of a few centimeters and only localized systematic discrepancies attributable to construction tolerances. These findings confirm the high geometric fidelity of the reconstruction and support the credibility of the restoration process. Beyond the specific case of the Old Bridge, the study proposes a replicable and scientifically grounded framework for evaluating reconstruction quality, contributing to more transparent, objective, and accountable practices in post-conflict architectural heritage conservation worldwide.