Some of these would make great Planescape burgs.
http://io9.com/5540934//gallery/gallery/7 - this one would be an evocative location on the Upper Planes.
http://io9.com/5540934//gallery/gallery/16 - here's another interesting one with an Indian theme.
http://io9.com/5540934//gallery/gallery/3 - a citadel on the Lower Planes.
http://io9.com/5544325//gallery/gallery/16 - bonus picture of Rl'yeh by Marc Simonetti, for aberrations to haunt.
Some great stuff there - I loved the image of the church on the back of the tank - I am totally using that in a game.