Megaliths in Montana, USA
Andrew Barker, who is referred to as Dr. Dolmen, examined the Icycle Dolmen at Giant's Playground. He then charted several dolmens in the MM on his spread sheets which is a scientific authenticy scale he developed to rate dolmens all around the world.
Andrew concluded that several of the dolmens here rated in the 90 percentile as they have not been altered. Stonehenge rates in the 80 percentile as it has been rebuilt at least twice in recent history.