Leaving a mark in unlikely places

 Can you see these stacked stones?  We came around the corner of this ocean highway road recently and literally stopped in our tracks. What in the world?  Even our Australian host was astonished and clueless. We bailed out of the car to hike down to the beach for a closer look. As far as the eye could see inside this cove were stacks of stones, many small and short, but some quite large and tall.  Questioning other visitors as they were hiking back up yielded no definitive answers either. The