sentences:  Wales' geology influences farming practices and building stone choices but also planning of developments which must take into account ground stability and liability to flooding - geohazards which an appreciation of the geology can help deal with.South Wales has a written record of geological interest going back to the 12th century when Giraldus Cambrensis noted pyritous shales near Newport.George Owen in 1603 correctly identified the stratigraphic relationship between the Carboniferous Limestone and the Coal Measures.