I found some old test renders of Kraków I did in Blender.
The model is made using blender-osm plugin.
It uses OpenStreetMap data which is ridiculous good, it makes quite a few assumptions but it works great for blocking out cities.
If and when I have time I will try to create a better import, clean it up and upload it. My ultimate goal was to get it imported in UE4 but time ran out