I am absolutely obsessed with the idea of Stonehenge and well anything with no exact meaning just yet. I watched and read so many things and I do agree that it was a calendar but there is the exact same thing a little further away made out of wooden pillars. The stone represents life because the stone can never die while the wood would rot eventually. So at different seasons they went back in forth for festivals of rebirth and honoring the ones that died each year. Such an interesting topic. So cool!