As in: don't.
When exploring with a camera, it's easy to forget that not watching where you are going is a recipe for a bruising. I came upon this stairway while looking off to the side of the trail. Some small tickle in the back of my neck prompted me to look where I was going.
I'll be listening to those tickles a little more carefully for a while...
Shot with a 7D & 12-24 at 12mm, f5.6, 1/100th, iso 400.