Stairs are fascinating objects that you want to be safe, comfortable and easy to use. The Stair of the Week was started to show the kind of dramatic stairs that encourage people to use them instead of hopping on the elevator. However in the search for those stairs I often find stairs like this, where I wonder what even holds it up. The lower run of this stair is straightforward; it can be fastened to the wall. However the upper run seems to just float, a squiggle of steel. I would not have thought that you could do that.
It's in a work/live townhouse in Graz, Austria, designed in 2009 by Architonic.