We're delighted to share this event with so many people

Stephen Cleobury, Director of Music

Special enough to be bought by broadcasters around the world and to be syndicated to more than 300 radio stations in the US alone, thanks to an arrangement with Minneapolis Public Radio.

And, via the BBC World Service, the service can be heard from New Zealand to Nigeria, and from Barbados to Bangladesh.

"It's still enormously satisfying," King's College director of music Stephen Cleobury tells BBC News Online.

"When three o'clock comes on Christmas Eve, people hear the voice singing Once In Royal David's City, and they feel Christmas is beginning."

Genesis

The service, which is broadcast live on Christmas Eve at 1500 on BBC Radio 4, was first held on Christmas Eve 1918.

Henry VI laid the chapel's first stone in 1441

Its genesis was in a wooden hut in Truro, Cornwall, where since the 1880s the Christmas Eve service had consisted of nine carols alternating with nine lessons - read by an ascending series of church figures, starting with a chorister and ending with a bishop.

The rather humble purpose of the service was to keep men away out of pubs on Christmas Eve.

The new-style service was introduced to King's by the college's new Dean, Eric Milner-White, who served as an army chaplain during World War I.

War years

His experiences with rank-and-file soldiers convinced him that the Church of England needed to make its worship more accessible, and he saw the Festival of Lessons and Carols as a step in that direction.

The vaulted ceiling is world famous

The service was broadcast by the BBC for the first time in 1928 and soon became an annual fixture - even during the war years, when the chapel's glass had all been removed and the name of King's could not be broadcast for security reasons.

The King's College choir was founded by Henry VI and has been in existence longer than the chapel building itself, which was completed in 1547.

The line-up of 16 boy choristers has stayed at the same numbers since 1440, and is supported by the adult voices of King's College undergraduates.

Legendary

The Festival has boosted the reputation of the choir enormously, leading to regular foreign tours and, since 1927, many commercial recordings.

Many ex-choristers have gone on to be influential figures in the music world, including Roy Goodman, renowned for his performance as treble soloist in a legendary recording of the Allegri Miserere, who has since made his name as a conductor.

King's College Chapel: "One of the great rooms in architecture"

The baritone Gerald Finley, countertenor Michael Chance and tenor Robert Tear are all in the front rank of international soloists, and five of the original King's Singers met at King's.

But the Festival of Lessons and Carols remains bigger than any of the constituent parts.

It is an event which yearly breathes new life into the extraordinary stone-vaulted chapel, which architect GE Kidder Smith described as "one of the great rooms in architecture".

'Anticipation'

"It is a most remarkable building, and has a very special acoustic - but it's even more remarkable on Christmas Eve," says Mr Cleobury.

"In the chapel you get a great, a palpable sense of anticipation before the service."

For Christmas Eve this year listeners can look forward to three specially written poems by Michael Symmons Roberts and pieces by Bruckner and Tavener.

And of course, there will be the carols, which by tradition begin with a lone choirboy singing the first verse of the carol Once In Royal David's City, unaccompanied.

"We're delighted to share this event with so many people," says Mr Cleobury.

"We get interesting and moving letters about it, especially from British people who find themselves abroad at Christmas."

King's College Festival of Nine Lessons and Carols is broadcast on Christmas Eve at 1500 on BBC Radio 4, and at 1650 on BBC Two.