Van Buren Stairs (click to enlarge)

This image is from the Martin Van Buren National Historic Site.  President Van Buren built this spiraling staircase to allow easy access between floors of the mansion.

The changing color as you rise up the stairs reminds me of a gradient fill in Photoshop (or even Excel).  I also like how the eye can follow the bannister and corkscrew around the image four times before arriving at the center.  This adds depth to the image, almost like you are viewing a tunnel that you could walk through.

It was pretty dark in the stairwell, and I did not have a tripod.  I ended up bracing myself against the wall of the first flight how stairs.

Martin Van Buren National Historic Site: N42 22 11.22 W73 42 15.03