Camera Clipping problem?

I'm working on a very large scene with very large terrain. If I use the mouse wheel to zoom into the scene, objects in the scene disappear. I tried changing the near clipping plane but it didn't work. I'm trying to put small cubes on the scene. The size of the terrain is about 2000 units by 2000 units.

 

You can't directly control the near and far clipping planes of the editor scene-view camera, but they are adjusted dynamically depending on what object that you last focused on.

Press the "f" key to have the camera move to focus on whatever object you have selected. If you focus on a small object then the camera clipping will adjust to something appropriate for viewing small objects up close.

 

If you are having issues within the editor, press "F" to focus. This saved me a lot of headaches when I was seeing object disappear when zooming in on vertices while in the editor.