Large free stones

 

This is fun -- on Facebook Market Place.  Glacial erratics in Kilgetty, not far from Tenby?  Free to good home.  I might just try to find out how they got to where they are now.......... and what they are made of.......

I wonder if there was an equivalent system back in the Neolithic?  I can imagine a message put out on the bush telegraph from our ancient ancestors in Preseli:  "Assortment of rubbish stones that are getting in the way of our development plans.  Free to anybody who cares to just come over and get them......"