As told by one of the musicians featured on the song...
The Fairytale of New York is the most played Christmas song of the 21st century and although you've heard it thousands of times, have you ever noticed that it features a harp?
We hadn't either until harpist Siobhan Sheahan shed some light on her story behind the iconic tune.
Siobhan and her dad John Sheahan (Irish musician, composer and former member of The Dubliners) joined Dermot and Dave to chat about Irish music in the rare ould times.
There's everything from Siobhan being handed the Fairytale Of New York demo cassette at U2's The Edge's birthday party in London, to Kirsty MacColl landing the vocals by pure chance, to the Dubliners recording 'The Irish Rover' with The Pogues in 3 hours, both Siobhan and John have some incredible stories.
Check out their storytelling in full by pressing the play button on screen.