This is a 3D Model with three morph targets. Each target can be set from -200 to 200 so you can get a variety of terrains or uneven land areas by setting each target and combination of multiple targets. Besides the Morpher modifier, other modifiers are in the modifier stack so that you can play with them if you like.
I have not used any texture. Just used procedural Mental Ray Landscape map. Since Mental ray is now a part of 3DSMax you will have no issue with this map. But, I think you will obviously like to use your own material.
Both animated and non-animated version of terrain models are included in the Max file.
I have included here also a preview AVI file for the animated one.