Devil's Churn, at Cape Perpetua State Park. The rock is Yachats Basalt, and composed of breccias and dikes in this area. The Churn is developed and eroded along a small fault, and I'm standing over a sea cave eroded into its end. While this is a spectacular spot, caution is warranted. The rocks can be slippery, and if you were to fall in, the only way out is to fight the turbulent water to the end of the head. I've always felt this would be a wise spot for a coil of rope for emergencies. On the other hand, I've never heard of any accidents here. Dana for scale in upper left. Photo unprocessed (other than rotating it). September 21, 2010. FlashEarth Location.