That's like asking what is the most famous thing in the USA - six people would give you six different answers. One famous thing is the Eiffel Tower, some more are: Notre Dame de Paris, the Bordeaux...
there are lots of famous vineyards, and not always big ones.
Some famous and very expensive wines (Château-Margaux, Château-Cheval-blanc, Petrus, Château-Lafitte-Rotchild, ...) are brand names...