This photograph of the Yellowstone River Canyon was made from the lookout at the Lower Falls, in Yellowstone National Park.
The morning sunlight streaming through the waterfall's mist makes a light rainbow cloud in the foreground. The sunlight is just reaching the river below in a few spots. This is the fabled "river of the yellow stone," legendary to Indians and Mountain Men alike.
Photo location: Lower Falls of the Yellowstone River, Yellowstone National Park, Wyoming.