By 'terrain view' you mean DEM i guess and for that you need to add the gmapdem.img specific to the mapping area you are using.

For 3D buildings you also need gmap3d.img. Included in many CN's are polygons showing building outlines (2D).

PS: I wasn't cranky about the way you asked the original question. I should have worked out what you meant by the context. My 2nd reply was meant to be humorous/lighthearted but sometimes that doesn't get conveyed in my written words. (Short version - NP).