I have just started working with a tablet and am interested in concept architecture, I must say that I am a bit lost when it comes to where to begin. I really enjoy this piece and hope that I can work my way to something even a fraction as good as your work.
I've spent 15 minutes staring at it and trying to catch all the little details. The arc at the top could use some more texture though, it looks quite flat - especially when compared to the rest of the image. Very impressive work.