In Spain, people traditionally eat grapes at midnight, one for each of the 12 clock chimes.
The custom is known as the twelve grapes of luck, or las doce uvas de la suerte. Each grape represents one month of the coming year, and finishing all twelve in time is popularly associated with good fortune. Families and friends often prepare twelve grapes in advance so they can follow the chimes without stopping to count.
The most famous public version takes place at Madrid's Puerta del Sol, where the clock of the Real Casa de Correos is broadcast nationwide. The sound sequence includes warning signals before the twelve principal chimes, a detail that helps viewers avoid starting too early.
The tradition became strongly established in Spain in the early twentieth century. It is now also practiced in several Spanish-speaking communities outside Spain, though exact customs differ from place to place.