Like the dioramas, I I started making these cityscapes in 3D a few years ago. I have always drawn cities with increasingly fine pens, and embellished them with my own details.
I set up the basic forms in pencil, and then start drawing with black fine liners ranging from 2mm til 0,01mm. I use a magnifying glass to see what I'm doing! All the buildings are hand cut, and the drawings are drawn individually not copied. So each picture is entirely unique.