At my grandparents we used to always go walking in the desert behind their house and collect ammo shells. There were always refrigerators, cars, just misc stuff back there that was used as target practice.
Take what I say with a grain of salt, because that's all it is compared to the ocean of complexity when it comes to actions and real life.
Yup. As soon as I learned to bike as a child, I was off. By the time I was thirteen, there were days in the summer when I'd just go and bike 20, or 30 miles away from my house and back again. I found lots of roads and places I never knew about before. I have a near perfect mental map though, and never once made a wrong turn/got lost when exploring, I always knew my way back.
Lately I've been really into hiking and alpine touring. I've hiked almost every trail I know of in the Presidentials, and lots of the Long Trail in VT. However, none of that compares to AT skiing, especially when I was out in Tahoe. In essence, it combines motions of cross-country with downhill skiing, and allows you to climb relatively easily, more easily than walking. What's so nice about it, is you really can just see a mountain you like, and go climb it, and ski it, or trek wherever. (Assuming you know basic avalanche safety.)