When the MTA set out to revamp Grand Central-42nd Street Station, the design challenge wasn't just engineering, it was helping 400,000 daily riders feel the difference. As Visualization Lead, I managed the team to build a fully immersive VR environment anchored by a MassMotion pedestrian simulation, giving designers and stakeholders an agent-level walkthrough of the station before a single wall was touched. Crowd flows, congestion hotspots, and wayfinding performance could all be tested in context, driving real design decisions rather than assumptions. What made this project stand out was the depth of integration across disciplines. Architectural geometry from Rhino, lighting from DIALux, and wayfinding signage from Illustrator all came together in 3ds Max alongside acoustic recordings captured live inside the actual station, mapped to the agent's path through the virtual model. The result was a photorealistic, fully ambisonic experience rendered in Arup's SoundLab that put every discipline's work into a single human-scale perspective. Wayfinding designers used the first-person walkthrough to validate and revise their signage plan against real crowd behavior in a spatially complex environment, producing a stronger final design before construction ever began. -------------------------------------------------------------- Data Stack: BIM | Pedestrian Simulations | Photometric Light | Spatial Audio | Unity3D