While traveling to Yellowstone National Park, I took this scenic byway out of Ashton, Idaho. I stopped first at the Upper Falls and was very impressed, then went to the lower falls, which were nice, but you needed a telephoto lens to capture them.
As I was taking a picture, a gentleman suggested I return to the upper falls to see the rainbow. It only pops out between 9 and noon, which makes sense as the canyon walls are high. So I returned to witness this fantastic site and was fortunate to capture this photo.