The Zeltinger Sonnenuhr the sundial vineyard is one of the Mosel’s monuments: a wall of blue slate so steep that picking it is closer to rock climbing than farming. This is Selbach-Oster’s Grosses Gewchs, the dry wine from their best mid-slope parcels, including vines still growing on their original ungrafted roots. It rests on its lees for the better part of a year, which gives it a breadth and texture you don’t expect from a grape this high-strung. Dry Mosel Riesling at this level is a serious wine, closer in ambition to grand cru white Burgundy than to anything sweet. Give it air now, or give it five years and be rewarded.