Hiking North Mountain Preserve

Stop And Turn Around, North Mountain Preserve, Phoenix

Below is a photo series of North Mountain Preserve in Phoenix. I carry my camera on every hike and am blown away at how the terrain changes from one peak to another. You'd think there'd be similar rocks and cacti, but it's never the same. (Which is kind of relieving to me). Each hike is an exploration, which is what truly makes it interesting to me. 

I'm going to invest in a book on rocks. I'd like to know what these petrified-looking pieces of earth really are. Maybe if I knew their names, I wouldn't find them as interesting...