The objective of this project was to produce a three-dimensional (3-D) photo-realistic virtual reality (VR) model of the Martian surface for use in the Mars Pathfinder mission. Marsmap, the interactive terrain visualization system, creates and renders digital terrain models produced from stereo images of Mars' surface taken by the lander's images for Mars Pathfinder (IMP) camera. A primary benefit of using VR to display geologic information i s that it provides an improved perception of depth and spatial layout of the remote site. The VR aspect of the display allows an operator to move freely in the environment, unconstrained by the physical limitations of the perspective from which the data were acquired. Virtual reality also offers a way to archive and retrieve information in a way that is easily understood. Combining the VR models with stereo display systems can enable a feeling of presence at the remote location. The capability, implemented in Marsmap, to interactively perform measurements from within the VR model, offered unprecedented ease in performing operations that are normally time consuming and difficult using standard photogrammetric techniques. This ground-breaking project demonstrated the power of using VR as a cartographic tool.