Visions of Hecatomb II
Nils nihils illustrations hecatomb 4
Nihils illustrations hecatomb 2
Nils nihils visions of hecatomb 1

Some rough concept for a fururistic city with several floors so high it seems there is a sky between them. More finished work for that here: https://www.artstation.com/artwork/vision-of-hecatomb