Good point. But this was also thousands of years ago. Would the solstice alone without navigation tools be that precise? And there is also the question of mechanicle ability to move and place the stones.
So the stonehenge is actually an advanced version of a sundial. Which was used (in my understanding) as a means of pagan sun worshipping. But again, given the time reference, it was pretty advanced knowledge.
I’ve also heard that there is an inscription on the well known stone hedge (regarding population) to 500 million. And I’ve heard some link this to the illuminati and new world order references. Bill Gates being perhaps at the center.