Mesh to Terrain contains Component to quickly convert 3D terrain model created using 3DMax, Terragen or any other editor to Unity Terrain.
• Supports Unity v5.2 – Unity 2018.x
• Unlimited number of models and terrains used in the component;
• Terrains are created in the same place where the meshes;
• Convert the textures of models to textures of terrain;
• The seamless result, when working with multiple terrains;
• Manually adding models or automatic detection of all models in the layer;
• No need to manually add the components of physics;
• Works with Relief Terrain Pack (optional);
• Built-in update system.
Asset Store Link – https://assetstore.unity.com/packages/tools/terrain/mesh-to-terrain-7271