This may sound absurd to all of you lucky riders in Colorado, but here in Corvallis, Oregon, finding good rock natural is almost impossible (because of all the silt brought into the valley by the Willamette river). Anyway, I was wandering through the geography building on the OSU campus while on my way to class and noticed a gigantic geology map with a huge key or legend. So I was looking over it and looked at the key and found some incredible places in this part of Oregon to ride natural. You can even look for specific kinds of rocks, I wanted something really grippy so I talked to some rock climbers and found some of the best natural I've ever seen. These are pics of the lines of rocks in a local park; this is the kind of stuff I had to ride before I looked at a map.