Discrete event simulation is broadly applied in the analysis of dynamic and concurrent systems and often with complex and detailed models. The process of creation and coding a non-trivial simulation model is error prone and the identification and understanding of what really goes on in a simulation run needs adequate tool support for makeing verification, validation and debugging productive. This holds in particular for the analysis of simulation traces, a powerfull debugging aid with the challenge of large amounts of data. In this paper, we present Traviando, a Trace Visualizer and Analyzer from Dortmund university.