Just to add to the thread Clyde, there is an interesting book by Richard Bradley,' An Archaeology of Natural Places'; in which he describes in the beginning the Saami siejdde - a natural rock shrine place - places they encountered as they followed their reindeer.
Stone and tree worship, both often representing certain shapes, maybe man or animal, is a fascinating subject, the Saami seem to have carved the boles of trees and would upend them, which is very similar to our Seahenge tree within the circle.
Petroglyphs are a storytelling mechanism, but our cupmarked ones always seem to be telling the same story ;)