This is a paid asset, but now you can download Industrial Zone – Mobile optimized Free.
Detail this asset from Unity Store: Original Link
Industrial Zone – Mobile optimized v1.0
This package contains a industrial area based on modern industrial theme. This is mobile optimized having low draw calls and low triangle count. It is easy to use. Average triangle count is of each building is from 400 to 1200 tris.
There are 82 unique props prefab are included to use. Those prefab contains buildings, machines , props etc.
Package includes
complete industrial scene
Two Lighting condition
Two skybox
Particles
25 building
18 machine buildings
4 trees and bush
35 props
Materials are easy to change. There are only 5 materials has been used for the scene. Road and vegetation Textures are 2048×2048 and others are 4K resolution.
Scene models are in single mesh and divided in many parts to reduce draw call