This is some work I have been doing during the writer's strike:
The Fortress City
The Tenement City
In theory this is what is at the other end of the train line in the one above.
I am working from a little bit of a story lline in my mind, just to make the whole thing a little more interesting.
Both of the above sketches were done mostly in the program Painter and
both started with a scanned pencil sketch.