24 July 2016 is a very special day in the world of vocal timepieces: it marks the Speaking Clock’s birthday. This Sunday, the talkative ticker will be 80 years old.
BT is marking this momentous occasion by looking back at its history and celebrating the voices that made it so great.
The Speaking Clock first came into being in 1936 in just the London directory area, as one of the first ever pre-recorded information services in the country. It came into being in the Post Office Engineering Research station, in Dollis Hill in North London, with the time coordinated from Greenwich meantime signals.
"The BT Speaking Clock is a national treasure," David Hay, head of BT Heritage, said. "Even though we live in the digital age, more than 12 million calls are made each year to the BT Speaking Clock to get an accurate time check."
Over the years it's had four permanent voices - Jane Cain, Pat Simmons, Brian Cobby, and Sara Mendes da Costa - along with various temporary voices for special occasions. Sir Ian McKellen, Jo Brand, Gary Barlow, and Lenny Henry have all lent their vocals for Comic Relief and Sport Relief.
Jane Cain, the first voice of the Speaking Clock
Current clock Sara Mendes da Costa got the job after winning a 2006 competition - a grand tradition in the Speaking Clock world, as original voice Jane Cain won a Post Office competition too.
These days, millions of us still ring it every year, and even Big Ben checks its own time by connecting with it.
To wish the Clock a happy birthday, dial 123 from a BT landline. Calls cost 38.9p per minute.