This paper presents the BioWIM, a multi-surface, multi-touch interface for exploring visualizations of complex biomedical environments using a semi-immersive virtual reality (VR) display. The BioWIM reinterprets the traditional world-in-miniature (WIM) VR metaphor within the context of navigating visualizations based on medical imaging data and using the unique capabilities provided by coupling a multi-touch table with a stereoscopic display wall. A "Window to the World" metaphor is used to navigate a detailed 3D scene displayed on the vertical surface by manipulating widgets and making touch gestures on top of medical imaging data displayed on the table. The technique supports navigation through complex environments while maintaining context. The results of a controlled user study comparing the BioWIM to a more traditional touch interface demonstrate improvements in accuracy in a compound search and size judgment task when using the BioWIM. An interpretation of these results and discussion of design principles and lessons learned is presented