Château Pétrus· Pomerol

There is no sign at Pétrus. You could drive past the plateau and never know that the most coveted Merlot on earth grows in the field beside you.

What sets it apart is underfoot: a button of blue clay, smectite, that surfaces here and almost nowhere else in Pomerol. Eleven and a half hectares of it, planted essentially to Merlot. The Moueix family has guided the estate since 1964; Olivier Berrouet has made the wine since 2008, following his father Jean-Claude before him.

I allocate Pétrus the way it is released, in small quantity, to those who understand what they are holding. It needs no embellishment from me. It is simply the reference against which every other Merlot in the world is measured.