About France's Public Holiday Calendar
Most of France's 11 public holidays fall on fixed dates, but four (Easter Monday, Ascension Day, Whit Monday, and the bridge days built around them) shift every year because they are calculated from the date of Easter.
Unlike in the UK, a French holiday landing on a weekend is not automatically moved to the next working day; instead, French workers often practice "faire le pont" (building a bridge), taking an extra day of leave next to the holiday to create a long weekend.