The Unity Editor includes a built-in set of TerrainThe landscape in your scene. A Terrain GameObject adds a large flat plane to your scene and you can use the Terrain’s Inspector window to create a detailed landscape. More info
See in Glossary features that allow you to add landscapes to your game. In the Editor, you can create multiple Terrain tiles, adjust the height or appearance of your landscape, and add trees or grass to it. At runtime, Unity optimizes built-in Terrain rendering for efficiency. The pages in this section explain the various built-in options available for Terrain, and how to use them.
Terrain