This is the fortress from underworld 3 within the Zbrush viewport. It is not displayed at the highest level. Each wall section has about two more subdivisions or so. Each wall uses out around 9 million or so polygons. The fortress buildings are just for stand ins so that I could sculpt around them. a lot of them were not the finished assets. A number of those buildings were made by other artists at Intelligent Creatures, and they used Maya to create them. I used Modo for the buildings, and Zbrush/ Clay3d for the rocks.