The scariest part was trying to set up my tripod and gear on a rock that had no guardrail. I was only about 12 inches from the edge and the edge included a drop straight down of over 1,000 feet (302 meters).
You are looking at the Colorado River above the Grand Canyon, so the water is calmer. The flow of the Colorado River through the Grand Canyon would have ferocious rapids.
Horsehoe Bend is a geological oddity because it obviously had to be carved by a rushing river, yet rushing rivers don't normally make big wide slow turns like the one in the photo. It shows how many millions of years had to be involved to carve a canyon with a slow bend like a horsehoe around the butte.
My photography tour continues tomorrow.