As early as the 16th century, the quality of Ay wines was recognised and recommended by the French king Henri IV. Most of the cellars and underground passages were dug in the 18th and 19th centuries. Of remarkable solidity, the cellars of the champagne houses were in fact used as shelters in time of war. In 1904, Ay saw the birth of the general union of Champagne winegrowers. Today, the vineyards of Aÿ-Champagne are included in the Unesco World Heritage list under the name “Coteaux, maisons et caves de Champagne”.