Placed by the waves or by humans? Doesn’t matter to me — it’s elegant and eloquent either way. It feels like a piece of dance, and the repetition of the form in the lower right-hand loop is extraordinary. Love the several triangles. And the shadows in the sand and the reflections in the water surface. I didn’t notice most of those things when I took the photo, just thought it was a graceful form. Noticing to take the picture is good; noticing more afterwards is a continuing gift!