What's your take on Stone Hendge?

The fact of the matter is they are not for sure they did not use machinery. Simple pulley systems were in use even as far back as early Egypt. Levers were probably used earlier than that. Not to mention a rolloing device where you would take 3-4 rounded logs, place the objevt on the log and roll it remove the logs as the object passes over it and take that log to the front of the object. It would take reletively little effort to move those stone like that. If nothing else you wrap the stones in rope and get enough people pulling on those ropes you can literally move anything as long as the rope holds. Why it was built? More than likely for Druid worship. Since any symbols (for the most part) have been erased due to erosion it would be difficult to say for certain.

I really don't know, all I read was that it was some kind of religious structure, from the ancient druids

It seems to be a calendar, is what I have read. It may also have had religious significance. I saw a show on PBS where a man and his sons showed how the great stones could have been lifted with very minimal man power by using simple engineering like fulcrums and gravity. I have always been fascinated by Stonehenge.