The Painted Hills are simply spectacular! The Hills are located around 2 hours NE of Bend, and are FREE. GO and take a bunch of photos!
The colors come from different soil types [and the metals in them], depending upon the moisture levels. With the various textures, colors and elevations, the area looks like a patchwork quilt.
Since the tones and hue appear to change from one visit to another, depending upon time of day [light] and moisture levels, we need to go back after it has rained, to see the difference in colors. Ralph said the last time he visited, there were more reds and yellows, this time more greens.