Urban planning often raises complex issues that are difficult to visualize and challenging to communicate. The increasing availability of 3D modeling standards has provided the opportunity for many developers, engineers, designers, planners, investors, and government officials to effectively collaborate to bring projects to fruition. Because of its real-time interactivity and widespread web-based content players, X3D proves to be a good choice for developing and visualizing 3D city content on the Web for planning purposes. Passenger rail is a viable and cost-effective transportation solution in many areas, especially in view of rising energy costs. The Savannah in 3D (or S3D) project is a multimedia tool for a feasibility study designed to bring passenger rail to Savannah; thereby opening up the historic, tourist-friendly city to a wider audience. The paper outlines the development process of an interactive 3D train model as it journeys from Atlanta to Savannah, Georgia - focusing on user interactivity and scene immersion to supplement the city and transportation planning agenda.