Just to correct an error of fact in JMD’s comment, as pointed out by a resident of Berwick St James. Whilst Winterbourne Stoke does indeed enjoy the benefit of getting free access to Stonehenge on a residents pass, the same isn’t true for Berwick St James as they were not part of the old Rural District of Amesbury at the time of the 1911 census. See http://bypasswinterbournestoke.blogspot.co.uk/2013/10/the-stonehenge-local-residents-pass-and.html for more details
English Heritage continue to try and put more and more conditions on use of these passes; conditions such as demanding you book in advance. None of these conditions have ever been tested in law.