November 25th is “Fete de la St Catherine”/Ste Catherine‘s day
Since the Middle Ages, women are under the protection of St Catherine. Each year one group of young women would make a beautiful headdress for the Ste Catherine statues. The group was solely composed of unmarried women, upon marrying, they would leave the group, hence "capping Saint Catherine" became, for a female, synonymous to "being still single at/after 25".
This custom survived in the trades such as dressmaking, fashion after they turned twenty-five. Women would attend a ball on St Catherine's Day in a hat made especially for the occasion. The hats must be extravagant and mostly bi-color Green and Yellow.
Green is the symbol of hope (hope to get married) and yellow is the symbol of wisdom, the one they acquired with their years.
This tradition was followed in every class, city or countryside.
Today, the tradition is still alive mostly popular in the fashion industry, hatmakers and fashion shops.