PN Triangles are on. I have just turned wire frame to see if anything funky is going on and found that the wireframe is also not displaying around the camera, but is further away.
It doesn't look bad but I have the feeling you're spending a lot of polygons on something rather simple, and it could be pushed a lot further. Got some wireframes?
Are you keeping this scene high poly, based on those wireframes, or do you intend to lower poly count of those objects? if intended as a playable game environment.