People traditionally eat 12 grapes at midnight in Madrid's Puerta del Sol during Spain's New Year's Eve celebration.
The custom is known as las doce uvas de la suerte, or the twelve grapes of luck. Participants try to eat one grape with each of the twelve clock chimes at midnight. The twelve grapes represent the twelve months of the coming year, and successfully finishing them is associated with good fortune.
Puerta del Sol is Madrid's central public square and contains the famous clock whose chimes are broadcast across Spain. The square's New Year's Eve gathering is therefore both a physical event and a televised national ritual.
The grape tradition is often linked to a surplus grape harvest in the early twentieth century, when growers promoted eating grapes at New Year. Accounts differ about exactly how the custom began, but its twelve-chime format is firmly established.