Madera Canyon is at the base of the Santa Rita Mountains, south of Tucson. It's one of our "sky islands." We've got a number of these small mountainous regions poking up from our desert floor, and they really are remarkable. The climate, flora and fauna atop these islands couldn't be more different than the Sonoran Desert. There are things like pine trees and snow up there! Each sky island is unique, since they are isolated from each other by the desert surrounding them. This was clearly demonstrated to me by the deer I saw that day. I have never seen a deer in the Catalina Mountains, north of town (including Mt. Lemmon.) I saw at least half a dozen on the 1 mile stretch of road in Madera Canyon.
Here are a few more pictures from my day.
Edit: I woke up this morning to this article in the paper about Madera Canyon.