Oh what a glorious place this is.  Avebury is much older than Stonehenge and encompassing about 30 square miles.  The queen of megalithic sites.   
I was a little appalled that a town had been built in the middle of this despite its age; but there it was.  I didn't get much time here, but it was certainly nice to be away from Britain's crowded cities if nothing else.  The standing stones are estimated to have been here for 5000 years.