Terragen - Terragen is a scenery generator, created with the goal of generating photorealistic landscape...
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!
MagicaVoxel - A free lightweight GPU-based voxel art editor and interactive path tracing renderer.
EarthSculptor - EarthSculptor is a realtime terrain height-map editor and paint program featuring an easy to use...
Vue - Create vast expanses of terrains, add trees, select the best point of view and render...
PnP TerrainCreator - PnP TerrainCreator is a highly integrated tool for large scale terrain creation.