Blender - Blender is the open source, cross platform suite of tools for 3D creation.
Terragen - Terragen is a scenery generator, created with the goal of generating photorealistic landscape...
Keyshot - KeyShot 3D rendering and animation software is the fastest, easiest way to create amazing, photographic visuals of your 3D models. Enter your search in the box aboveTryYour download of KeyShot is only moments away.
World Machine - Command powerful tools like erosion and advanced colormaps to create terrain heightmaps, meshes, and textures for your game or 3D scene. Download for Free!
Cinema 4D - Cinema 4D is a 3D modeling, animation, motion graphics and rendering application.
PnP TerrainCreator - PnP TerrainCreator is a highly integrated tool for large scale terrain creation.