It is one of the famous bell sounds in the world. As has been the case for a hundred years, the iconic sound of Big Ben will once again ring at midnight today to herald the arrival of the New Year and the famous ‘bong’ sound will be broadcast live by the BBC, with… thus reaching much further than London.

It was December 31, 1923, and as midnight approached, a BBC sound engineer climbed onto a roof opposite the British Parliament holding a microphone to record the sound of Big Ben’s bell for the coming of 1924.

Since then, the familiar sound has been broadcast live every New Year. So today at midnight exactly on BBC Radio 4.

This bass sound is heard twice a day on Radio 4, at 6pm and midnight, and also at 10pm on Sundays.

While Londoners celebrate the New Year, Andrew Strangeway, a 37-year-old watchmaker, will be at the top of the 96-metre-tall Elizabeth Tower, home to Big Ben and four other bells.

Along with two of his fellow watchmakers, Strangeway will make last-minute checks to make sure the watch will tell “the time accurately down to the smallest fraction of a second.”

“I think there is a small chance that things will go badly,” he tells AFP. “Our main concern for events like New Year’s is whether (the ‘bong’) will be heard and whether it will hit just in time.”

He declares himself excited to be “next to the bells (…) when everyone looks at the clock to start the new year”.

Big Ben sits atop the Elizabeth Tower – the new name given to the “Clock Tower” in 2012 to mark Queen Elizabeth II’s Platinum Jubilee – and was built in the 1840s.

The bell weighs almost 14 tons.

Before the renovation, watchmakers checked the accuracy of the time via telephones. The clock is now GPS-set thanks to the National Physical Laboratory.

However, the method for setting the clock remains traditional: old coins are used to add or remove weight from the clock’s giant springs, for the second’s accuracy.

“It’s a fantastic job,” enthuses Strangeway. When he walks around London, he can’t help but look at Big Ben congratulating himself thinking ‘yes, it’s still working’.