English: The Rosdorfer Baggersee is found to be not deeper than 23 m and so all sources on maximum depth of the quarry pond are most likely wrong. Although our approach is very simple and certainly many inaccuracies remain, our map is likely a much better source for the maximum depth of the Rosdorfer Baggersee than to just rely on unverified public claims on its maximum depth. Some sections of the pond's shoreline have extremely steep slopes and should not be walked on, as loose gravel can slide off and pose a hazard to recreationists. Our bathymetric map may be refined in future studies, especially close to the shore, where the steep edges may require a higher sampling intensity to assess the fine-scale changes in pond depth.