NewScientist.com also has articles about how bad global warming is (Global warming 'kills 160,000 a year').
OK, let's get this straight. A 'site' cannot be carbon-dated. A 'stone' cannot be carbon-dated. Only 'carbon' can be carbon dated. Forgive my irritability but every time someone discovers an earliest whatever, some jock wants to make the new record by 'discovering' an earlier one.
It's easy. Some where near the site (dig if you gotta) find some charcoal and date it. If it ain't a record, keep digging. Eventually you'll make it to NewScientist.com and who knows, if you can bad mouth dubya enough the Nobel people will give you cash money.
AND only when there is a regional correlation with dendrochonology. If there is no synchronized, overlapping tree-ring record for the area going back an appropriate amount of time, then any carbon dating is merely a guesstimate and may be wildly off.