Three Kings Day Tradition Spreads Across The Country. From East Harlem in New York to Disneyland in Southern California, many Latinos on Monday will celebrate a Christmas holiday that some believe is even bigger than December 25, the Día de los Reyes. Three Kings Day or Día de Reyes is January 6. This day is formally the Feast of the Epiphany on the church calendar, the 12th day after Christmas, when the Gospel of Matthew says the Magi arrived bearing gifts for the divine child, Jesus.