If you’re wandering the country on I-90, say to or from Sturgis, SD, a stop at the Devil’s Tower north of Sundance, WY, is very worthwhile.
Devils Tower
The identity of this geological oddity is the subject of some disagreement. Three theories of its origin are in play: 1) an igneous stock, 2) a volcanic neck, and 3) the remnants of a laccolith. Whatever the case, it is plain that the sedimentary rock surrounding it has long since eroded away to reveal the more weather resistant igneous rock.
Climber on Devils Tower
Close up, the columnar structure of the formation is evident. This feature speaks to a slow cooling process, one made possible for a magmatic body deep underground insulated by the surrounding formation.
Devils Tower, Wyoming, June 2010.
Lamentations on Chemistry 
When I was attending Gopher University, the student outdoor club would make an annual climbing trip each summer. The more experienced climbers would bring along tuxedos, don them on the summit and then greet other climbing groups on their arrival.
I don’t have the wirey build needed to be a good climber. Evererst would be more my style, but that is turning more and more into a Disney-like destination every year.
My problem with climbing is that I have to drag a fat middle-aged guy with me.