Detail this asset from Unity Store: Original Link
This is a paid asset, but now you can download Medieval City Free.
Medieval City v1.0
A medieval city environment built with Unity 5. Plenty of buildings are included as well as props and addon structures so you can create your own variations.
Included are albedo, metallic (with smoothness in alpha channel) normal, and ambient occlusion maps.
Music in the video is by Vertex Studio