When the river's water level is lower after the spring melt, these smoothly-eroded basalt rock formations reveal themselves. It's not easy, nor is it pleasant, reaching them.
Some pretty decent light occurred while I was attempting to find a way out to this spot in the river. I didn't expect to spend as long as I did finding a composition (hours), so it turned into a twilight shot. I think it works well due to the strange and perhaps otherworldly nature of the foreground.