Abstract built environment

I had to redraw this after a spilling accident. It took possibly eight hours total over the span of approximately two weeks to complete. This was for my art class, Studio art II: Drawing in North High School in Minnesota. I would have to say of the few I've personally showcased my artwork, this one, so far, has been a favorite. It still, however, could use some work. I rushed in the stairs and left wall to turn this in on time, making it incomplete in my opinion. There are several elements depict in it, and may I ask, what do you see in it?