<p>This study presents a 3D structural analysis of historic mine shafts at the Iwami Ginzan Silver Mine UNESCO World Heritage Site, integrating handheld LiDAR SLAM (Light Detection And Radar Scan Simultaneous Localization and Mapping) technology with conventional geological fieldwork. High-resolution 3D models of the Okubo and Ryugenji shafts were generated, enabling detailed visualization and structural interpretation. In the Okubo Shaft, six minor shafts were identified, predominantly trending NE-SW to ENE-WSW, alongside fractures and cataclastic faults striking E-W, NE-SW, and N-S. Fault surfaces commonly exhibit strike- and dip-parallel lineations, and mineralization, including silver and manganese veins, is closely associated with these structures. In the Ryugenji Shaft, a more complex network of fractures and sub-drifts were documented. Thirty-three sub-drifts, mainly trending WNW-ESE to NW-SE, and forty-nine fractures with dominant E-W to WNW-ESE orientations were identified. Field observations confirmed the presence of abundant cataclastic faults with well-developed slickenlines and associated silver-bearing veins. The 3D models clearly demonstrate a direct spatial relationship between sub-drifts and structural features such as fractures and faults. These findings highlight the critical role of structural controls in ore localization and emphasize the effectiveness of combining 3D imaging with traditional methods for documenting complex underground geological frameworks. Furthermore, the high-resolution models can contribute significantly to the preservation, risk assessment and visualization of key geological monuments in the geoheritage sites.</p>