Question: why is antzar eguna celebrated?
Answer: The Day of the Geese, also known as Antzar Eguna, is a competition held as part of the San Antolín festival in the Basque fishing-town of Lekeitio, in which participants attempt to decapitate a goose suspended on a rope above the town harbor. ... As a prize, the winner of the competition gets to keep the goose.