ARCHITECTURAL AND ENVIRONMENTAL CONTROLS ON LONG-TERM LIMESTONE WEATHERING OF COASTAL FORTIFICATIONS: THE CASE OF FAMAGUSTA (CYPRUS) VAUTIER Franck1, PHALIP Bruno2, TOUMAZET Jean-Pierre3, ANDRÉ Marie-Françoise3, VOLDOIRE Olivier3, FRONTEAU Gilles4, THOMAC

Stone decay affecting coastal fortifications is commonly interpreted as the combined result of material properties and environmental exposure, yet the respective roles of lithology, architectural configurations and long-term system evolution remain difficult to disentangle in multi-phase monuments. The fortified city of Famagusta (Gazimağusa, Cyprus) provides a unique case study to address this issue over a multi-centennial timescale. This study combines archival and archaeological analysis, multiscale Structure-from-Motion (SfM) photogrammetry, surface-based photo-interpretation, non-destructive field measurements (Leeb hardness and water absorption) and targeted laboratory analyses to quantify and interpret limestone decay across Lusignan (ca. 1300 AD) and Venetian (ca. 1500 AD) fortification phases.SfM-derived erosion-depth metrics and surface-based weathering indicators reveal strong spatial contrasts in degradation intensity, primarily structured by coastal proximity, wall orientation and architectural configuration. Despite similar environmental exposure, Lusignan masonry consistently exhibits higher erosion depths and surface weathering rates than Venetian masonry. Laboratory analyses and in situ measurements demonstrate that limestones used during both construction phases belong to the same lithological facies and display comparable intrinsic physical properties when compared at equivalent alteration states, ruling out a first-order lithological control. These results indicate that the observed reduction in decay intensity from the Lusignan to the Venetian period reflects a change in the response of the wall system to environmental forcing, driven by architectural reconfiguration, jointing practices and internal moisture redistribution, rather than a change in lithology or external forcing. This integrated approach highlights the importance of construction history and boundary conditions in interpreting long-term stone decay in coastal built heritage.