The special notice Clos, French word meaming closed, is printed on the label (decree of 19th August 1921) to indicate a Champagne produced from grapes, grown in a closed vineyards, which means surrounded by walls or gates. The original aim was to prevent animals to enter the vineyards and to damage them. Such walls were built by monks to prevent theft as well, or to create a micro-climate.
This also enabled the producers to harvest when they wanted and not when indicated by the decree. After the Revolution, another decree established that the Clos definition could only be used in case the vineyards was really surrounded by walls. This requirement was later abolished, when walls were damaged by weathercondition or over time.
There is still a lot of debate on this definition, especially as regards the possibility of preventing diseases... Only two vineyards in the Champagne region have survived the phylloxera. One is Clos Saint-Jacques and the other is Clos des Chaudes. They are both located in Aÿ (Vallée de la Marne) and are owned by Maison Bollinger. No doubt that these two vines could survive the phylloxera thanks to the walls. All Clos, around 30, represent only a small part – maybe 0,001 % - of over 80,000 hectars of vineyards in the region.
The most famous and representative Clos are the following: Clos du Mesnil (Krug) – Le Mesnil sur Oger, Clos d’Ambonnay (Krug) - Ambonnay, Clos Saint Jacques e Clos Chaudes (Vieilles Vignes Françaises – Bollinger) – Aÿ, Clos des Goisses (Philipponnat) - Mareuil sur Aÿ, Clos Saint-Hilaire (Billecart Salmon) - Mareuil sur Aÿ, Clos du Notre-Dame (Veuve Fourny) – Vertus, Clos Cazals (Claude Cazals) - Le Mesnil sur Oger