Madrid is the city where Spain's Puerta del Sol crowd traditionally eats 12 grapes at midnight on New Year's Eve.
The custom is called 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. Successfully completing the sequence is popularly associated with good fortune in the twelve months ahead.
Madrid’s Puerta del Sol is the best-known public setting for the ritual because the square’s clock broadcasts the chimes nationally. Families and public crowds across Spain also follow the countdown through television, so the practice is not limited to people physically present in Madrid.
The grapes are sometimes confused with a general Mediterranean New Year food tradition, but the distinctive feature is the set of twelve grapes matched to the twelve midnight chimes. The custom became especially prominent in Spain during the early twentieth century.