The bells of St Paul's Cathedral will ring out across the square mile this evening to welcome the newest addition to the Royal family, Princess Charlotte Elizabeth Diana.
A full peal of bells will ring out across the city from 5pm and the sound will be heard for four hours.
The performance, known as a peal, will be the 5021 changes of Stedman Cinques, a particular composition of ringing which includes more than 5,000 changes.
In a peal of 'Cinques' there are 11 working bells that ring the changes while the biggest bell, the Tenor, always strikes at the end of the row, giving a pleasing rhythmical effect, according to St Paul's.
"Organising and ringing full peals is not a trivial task under any circumstances, especially at St Paul’s where the largest of the 12 bells weighs over three tons. But add to that the uncertainty of the timing and things are even more complicated - we've had ringers on stand-by all over Southern England for a few weeks now. We're especially excited as this will be the first St Paul's peal attempt for a number of our ringers," said secretary to St Paul's Cathedral Guild of Ringers Dave Bassford.
A full peal is only successful if the bells ring continuously with no breaks for the full composition - something that's expected to take four hours. Any significant mistake would mean the attempt will be unsuccessful and not recorded as a full peal said the Cathedral.
One recent unsuccessful attempt at a full peal took place in 2013 in celebration of the birth of Prince George. The ringers failed to complete the full peal after a fire alarm caused the building to be evacuated after three hours.
The bells were also rung out for the births of Prince's William and Harry.
If successful, the peal will be the 101st recorded at St Paul's since 1881.