Inside King's College Choir ahead of Christmas services
For many people the Festival of Nine Lessons and Carols services from King's College Cambridge - either on television or radio - marks the start of Christmas.
The spine-tingling moment during carols from King's comes as a lone chorister sings the first verse of Once in Royal David's City to mark the beginning of the service.
BBC News went to King's College School to see the choristers rehearsing ahead of the big day, and to find out how the soloist is chosen.
Video journalist: Nikki Nahal. Producer: Verity Wilde
With thanks to King's College, Cambridge
You can listen to the services on BBC Radio 4 and BBC World Service at 15:00 GMT on Christmas Eve or watch on BBC Two at 17:25 GMT on Christmas Eve (UK Only)
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