This is a paid asset, but now you can download PBR Desert Landscape Free.
Detail this asset from Unity Store: Original Link
PBR Desert Landscape v1.0
PBR Desert Landscape is a 25km² Environment ready to use in your Unity Projects.
You can use this Asset for Surival, RPG, FPS or other Projects which require huge playable Areas.
The basic Texture layering, approximates real world Material behavior and is a good foundation to start your own Detail work.
The Asset is completely set up with Unity’s native Terrain-tools and works with real time GI and PBR.
Details :
Terrain:
– 5km x 5km x 0,8 km
– HD Rock, Cliff, Sand Textures (Diffuse+Normal)
– Heightmap & Splatmap
PBR Rocks:
– PBR Textures (Albedo, AO, Normal)
– Rock1 1100 Verts
– Rock2 700 Verts
Note: All screenshots where made by using only PBR Desert Landscape Package and native Unity Assets.