Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have established ‘Cosmowebportal’, a unique data center for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.