A very fanciful fortress, with Middle Age elements, as well as roman architecture (key stones in the arches, for example). But, unlike these two references, there are a lot of metal here, causing the need for a lightning rod in the center of the fortress. The round door gives to this fortress an exotic touch. It is doubtful that it would be functional in the real world. There are one only material with image texture. The others use procedural textures. The rendered images was made using Filmic to set the colors, with base contrast look.