I go through a very quick and easy way to create tiles of your city for 3D Printing.
To create a tile of your city you will need to head over to cadmapper:
https://cadmapper.com/
I use Sketchup Pro it has a free trial and you can get it here: https://www.sketchup.com/products/sketchup-pro
You will also need an extension Eneroth Terrain Volume and you can get that here:
https://extensions.sketchup.com/extension/71021899-fff7-44e9-87ef-14b79ecbd3b9/eneroth-terrain-volume
You can export from cadmapper to other programs but i have not used any of them as of yet.