http://rendering.ru/ru_en/splineland.html 

SplineLand is a plugin for Autodesk 3ds Max that helps to generate topographically accurate terrains from a set of splines and lay roads. Without SplineLand it is almost impossible to achieve such accurate results in 3ds Max. Now you can do it quickly, in just a few clicks your topographical data in form of splines can become a terrain.

Splines can be topographic contours in one plane each, or can be just any shape.

Features
Creation of precise and topologically correct terrains from splines representing topographic contours
Powerful algorithm which allows to control level of details only in areas you need, just by adding or subtracting splines in that particular area, without overloading the whole scene
Possibility to use any types of splines, including open splines
With SplineLand you can lay roads over the terrain as well as create and level areas, generate bedding courses and ground cuts at selected angles and heights
Possibility to assign ID to various terrain details
Control over grid density