This master’s thesis conducted a comparative analysis of spatial data obtained from three different sources, using Grad Castle in Goričko as a case study. The analysis examined photogrammetric survey data, airborne lidar data, and data from the Cyclical Laser Scanning of Slovenia (CLSS). The purpose of the research was to assess the geometric consistency, completeness, and thematic accuracy of the individual data acquisition methods and to verify their usefulness in documenting cultural heritage. From the measurements taken, we created a georeferenced and classified point cloud for comparison between the methods, and produced a digital terrain model, orthophoto, and 3D model as byproducts. The M3C2 method was used to compare the point clouds. The comparison of digital terrain models was performed by subtracting them from each other. We also analyzed the density and completeness of the data on selected parts of the object and the accuracy of point classification across the entire point cloud. The results showed that the aerial laser scanning method provides the most spatially uniform data capture. High thematic accuracy of the point cloud classification was also established. Using UAV photogrammetry, we obtained a very dense point cloud with well-captured object details. Nevertheless, gaps appeared in the point cloud in some places where no data was available. The CLSS data represented a good reference source for comparing digital terrain models, as it has a uniform point density in the point cloud, but a lower spatial resolution. The study confirms that the most suitable method for documenting the Goričko Castle, which stands on undulating terrain surrounded by vegetation, is aerial laser scanning using UAV.
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