Icelandic families often associate the taste of Christmas with two popular local sodas mixed together. That’s because combining Malt and Appelsín to make jólaöl, or Christmas ale, is exactly what they do over the holidays.

Ölgerðin brewery, founded in 1913, manufactures both the soft drinks that make up Christmas ale. Originally, they touted their debut product, Malt Extrakt, as a stomach ache cure. Today, adults and children alike down the mildly alcoholic (1 percent ABV) Malt year-round, but it’s especially popular as a complement to holiday food. In 1955, Ölgerðin released Appelsín orange soda, which quickly became one of the most popular soft drinks in Iceland.

Malt and Appelsín are enjoyed separately all year long, but jólaöl is a Christmas special. The blended brew offers the fruity richness of an ale without the holiday hangover. Families concoct their own versions at home with specific ratios of each soda. Less particular fans buy plastic jugs of the premixed drink, which is known as Jólabland, or Christmas mix. No one is sure how the union of Malt and Appelsín became such a staple at Icelandic Christmas, but that doesn’t make it any less fundamentally important to partying steadily through the darkest month of the year.