We could, of course, say "Preuilly sur Claise" and leave it at that, but it would only lead to further questions. Or we could answer "the South Touraine" but like most of the answers available that presupposes a knowledge of French geography (the French is "Touraine Côté Sud", but that additionally requires careful use of a French accent). "Touraine" is also accurate, but of a pre-revolution nature. Even more pre revolution would be the answer "in the Duchy of Guienne (Aquitaine)", but at some time it was also in the County of Anjou.
A more modern answer - Indre et Loire - is also correct, being the département that Preuilly sur Claise is in - but what does it tell anyone who doesn't know France well? If were were in Normandy, people would instantly form an idea - somewhere up north, on the D-day beaches with cider and calvados. Or even Dordogne - in the middle with rivers and caves with rock paintings and stuff. Indre et Loire has no resonance like that. Centre - the region we are in - means even less.
So: What we tell people is that we are at the edge of the Loire Valley. Geologically, politically, historically and ecologically this is correct. It also gives people an idea of where we are - somewhere in the middle, sort of on the left hand side.
It's just that we aren't actually in the valley of the Loire river itself...
Simon
Maps from Nationmaster