The Portage-Fill Harmonic Holiday Concert will take place at 7 p.m. Sunday, Dec. 15, at Vashon Theatre — an evening hosted by Vashon Island Community Church that will benefit the Interfaith Council to Prevent Homelessness.

For 51 years, Portage Fill has entertained islanders with tunes from the great American songbook, bringing jazz and swing tunes to stages all over Vashon, including Ober Park summer concerts and too many Strawberry Festival street dances to count.

According to trumpet player Lou Engels, the group’s first practice took place in his home. The year, “the best we can remember,” he said, was 1973.

Originally a small combo started by Engels’ neighbor, pianist Bill DeGleria, the group was christened the Portage Fill-Harmonic. It later transformed into a big band under the direction of Seattle trumpet player and Vashon music store owner Monte Sewell.

Pete Welch, of Vashon Events, thinks that the band’s popularity stems from its ability to get people of all ages up and dancing.

“They always draw a crowd,” he said, commending the instrumentalists, as well as the singers, Maggie Laird and Lou Mangione.

“When Lou and Maggie get up there, it is almost like you are stepping back in time. It’s just beautiful. They’re crooners,” he said.

Youths under 18 will be admitted free, with other tickets being sold for a suggested donation of $20. Get them at the door or in advance at vashontheatre.com.