>>614056wow, good call.
yes, the grotto is shown on the wiki page for Tobermory, no question you are right.
I've been to Superior where the petroglyphs are, and Awenda Provincial Park on Huron, but mostly I've been on the Michigan side. I knew that open, blue water without ocean-sized waves, all those pine trees, and those rock outcroppings had to be one of the Great Lakes. The rocks in OP look more like what I saw by Superior but some of the ones up there were still in the shape of the lava, not just jagged and broken. Beautiful country on those shores, all of the lakes. very special country.