This paper presents a user study that investigates2D and 3D visualizations of bar charts in geographic maps.The task to be solved by the participants in this studyrequired estimation of the ratio of two different spatial distancemeasures and relative ranking among potential candidates. Theresults of this experiment show that subjects were equally fastand accurate when using both the 2D and 3D visualizations.Visual discomfort was reported by almost half of the testpopulation, but performance was not affected. Our study alsoshowed that frequent game players did not benefit more froma 3D visualization than inexperienced game-players.