Prehistoric Eddy Hole

This hole, on Seurasaari Island in Helsinki Harbour was made during the retreating ice age when the waters caused a small rock of granite to become trapped in a swirling eddy from which it couldn't escape. Over time it simply wore a hole into the larger granite block below and this is the result. It's difficult to even imagine the forces and the time involved. Mrs. Joesblips was suitably impressed as you can see.