Thought that might get your attention Goff :-)

Not to mention Layamon's poem, Brut, of 1215 where he writes of Stonehenge

The stones are great
And magic power they have
Men that are sick
Fare to that stone
And they wash that stone
And with that water bathe away their sickness

The operative words being fare, stone and wash - ie travelling to the stones to wash them, and with that water a sickness away.

There are similar rites still practiced in some parts of the world, where stones are washed in an act of purification. Perhaps something similar was also going on at Avebury and Silbury, with their abundance of streams, rivers and wells.