I feel a bit like Gary Snyder today (and I am paraphrasing, and probably badly):  the bend of the waist, the articulation of the knees, the in and out of ragged breath, the crunch of boots on ground. 
Hiking.  I know I wax romantic, and some of you, probably a lot of you, don't understand it or even want to.  It's dirty, it's cold, it's hot, it's sweaty, it's exhausting, it's blister-inducing.  You stand at the bottom of a hill and think, "no way am I walking up that thing."  But then you do, one boot in front of the other and when you look behind you, you think, "I climbed that."
I love the austereness of it, which is probably why I prefer to hike alone.  It seems sacred to me.  From an online dictionary:  "Austere usually implies a purposeful avoidance of luxury or ease."  Maybe, to me, it seems as if you haven't earned it if the process wasn't difficult.  I am leary of things that seem to come very easily.  They rarely do. 
When I am on the trail, I don't think about subway trains packed full of people, bills that are due, or any of the riff-raff periphery.  I walk, I breathe.