How to render a large sized scene ? ( far objects are not rendered).

Well i am making a render of an airport, so there is some baggage handling in the scene.
Also there is a window, and behind that you can see the airport, there are several air-planes, in the distance.
But they are not rendered ?, large objects are rendered till a certain distance, after that they vanish in gray ??

How could i render this entire image including the long distance view through the window ?
Is there somewhere a limit that i can change ? (it happens in both cycles and blender renderer).

In the camera settings you can set the start and end clipping distance for the camera view

In the properties panel (shortcut N) you can set the start and end clipping distance for the 3d viewport

thanks i didnt knew that