We propose to set up a European digital repository for cosmic ray databy pooling existing data archives and by developing a real-time databasewith the data of as many European neutron monitor stations as possible.The data will be available through internet. Cosmic rays provide adiagnostic tool to analyze processes in interplanetary space and at theSun. Cosmic rays also directly affect the terrestrial environment andserve as indicators of solar variability and non-anthropogenic climatechanges on Earth. In the fifties of the last century a worldwide networkof standardized neutron monitors was developed to examine temporal andspatial variations in our space environment. Despite decades oftradition, neutron monitors remain the state-of-the-art instrumentationfor measuring GeV cosmic rays that cannot be measured by spaceexperiments. Therefore the worldwide network, which presently consistsof about 50 stations, ideally complements cosmic ray observations inspace. Since the beginning of the coordinated neutron monitormeasurements the data have been collected in world data centers. A bigshortcoming of these data centers for today's demands is the fact thatthe data are not available in real-time and only with a time resolutionof one hour. Cosmic ray applications, e.g. space weather warnings(geomagnetic storms, solar energetic particle events) need access toneutron monitor measurements in real-time and with high time resolution.Reliable forecasts of geomagnetic storms are important in many technicalareas (radio communication, electric power lines, etc.). Confident alertprediction of solar energetic particle events is highly important formanned space missions and for airline crews and passengers. The proposalunifies for the first time the cosmic ray community of the Europeanneutron monitor network in a coordinated effort to advance the use ofcosmic ray data in cutting-edge applications, as e.g. space weather.