One of the most important traditions of Día de los Reyes is the Rosca de Reyes or the Wreath of the Kings.
The Rosca de Reyes tradition consists of baking a cake (which symbolizes the King's crown) with a baby Jesus figurine hidden inside. Whoever gets the slice with the figurine must host a part on February 2nd.
The celebration of Día de los reyes commemorates the coming of the Magi to see baby Jesus and is the Spanish way of celebrating the Epiphany.
http://www.latintimes.com/what-dia-de-los-reyes-6-facts-about-three-wise-men-day-latin-america-361829
http://www.elboricua.com/losreyes.html
http://www.hermamas.com/2015/01/dia-de-los-reyes-magos.html
http://tropicasa.com/blog/2017/01/05/the-meaning-of-the-rosca-de-reyes/
http://stpatricksoho.org/blog/2015/01/03/music-for-the-solemnity-of-the-epiphany/
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