The cellars beneath 52 Rue de l'Arbre Sec were dug to hold the private stock of a royal wine steward, not to teach anyone anything. They belonged to the household of Louis XV's sommelier, Sieur de Chaumont, whose responsibility was the crown's cellar at the Louvre a few hundred metres east. The vaults were cut into limestone quarried from the same seams that raised the palace itself. Stone was taken out; bottles went in. The address sits in the 1st arrondissement, on a street whose name — Arbre Sec, the dry tree — predates the Revolution by centuries. Above ground, the quarter has been rebuilt repeatedly. Below, the temperature holds near 13 degrees year-round, without machinery. That stability is why the cellars survived as working storage long after the monarchy that filled them did not. A wine tasting course paris visitors take here is conducted in rooms that were engineered, accidentally, to be perfect classrooms for the subject. What the cellars now house is a sequence of themed rooms organised by French wine region, each treating a different element of viticulture: terroir, grape variety, vinification, and the sensory vocabulary used to describe the result. Bordeaux, Burgundy, the Rhône, Champagne and the Loire each hold their own vaulted alcove. Aroma stations isolate individual scent compounds — cassis, leather, wet stone, vanilla from oak ageing — so that the language of the sommelier stops being abstract. Displays cover cooperage, cork, phylloxera, and the 1855 classification. The self-guided audio tour and entry costs 29 EUR per person. Paris is not a wine city in the way Beaune or Épernay are. It has no significant vineyard beyond the ceremonial rows at Clos Montmartre. It is, instead, the place where French wine was priced, argued over, exported and codified — the commercial and critical capital rather than the agricultural one. Négociants kept offices here. Classification systems were debated in Parisian rooms. The cellars, in that sense, are geographically honest: they teach the whole country from a single subterranean vantage point. Elsewhere in the city the same subject is approached differently. Montmartre pairs it with cheese counters; other formats put a chef sommelier at the head of the table. But the underground rooms remain the reference point, and the wine tasting course paris travellers most often mean is the one held under the Rue de l'Arbre Sec, in the dark, at a constant thirteen degrees.