Purpose: The aim of this paper is to present a computational method for identifying bottlenecks in the rail transportation network under the assumption that a modal shift from road to train should be emphasised. Methods: From a methodological point of view, the contribution is twofold: First, an estimation of the overall freight transport in Europe is done. Basic statics, as available from countries and the European Union, are utilised to estimate the actual freight transport demand between NUTS3 areas in Europe. Second, the (theoretically) needed train transports are computed by finding the shortest route between two NUTS3 regions. If the capacity of the train network is reached on a specific strech, alternatives are searched. Results: To assess, where bottlenecks are, we used the European rail network (from OpenStreetMap) as well as intermodal terminals (provided by a project partner) for our computations. The results show that our approach is working. Conclusion: The method presented within this paper is easy to use (only a few input data are needed) and fast (with respect to computational effort) such that it can be easily used for infrastructural planning tasks and assessing whether envisaged extensions of the rail network contribute to the higly desired modal shift.