Grinnell Peak in Glacier National Park, Montana at about 5:45 AM. The partial sideways sunlight along with it's already reddish rock causes this radical effect. Here's a brief article link about how nobody believed another photographer's photo of this occurrence was real (especially the commenters). It most certainly is.
The Many Glacier Hotel celebrated it's 100th anniversary 3 weeks before this photo. After filming a movie here the late Robin Williams once said of it, “If this isn’t God’s back yard, then he certainly lives nearby.”