Visual Terrain Maker is a 3D-Modeling program allows visually create landscapes (maps) for games or other purposes. It is a freeware terrain making application.
Here is a screenshot to illustrate the features and user interface of this application:
Program allows create 3D landscapes. Screenshot of Visual Terrain Maker - 320px · 240px
GstarCAD
Autodesk Fusion 360
Autodesk Design Review
3D Object Converter
LibreCAD