As a part of an ongoing investigation into the potential role of cyber-physical models in architectural design studios, a prototype which enables to visualize a space from eye-level was designed and implemented. The user sees an urban environment as a hologram using a Head-mounted Display (HMD) in 3D. A small physical marker helps to visualize the space from a given viewpoint at eye-level. By moving the marker users can intuitively explore the space regardless of specialized knowledge required to manipulate 3D models.