At daybreak, whilst most Londoners remain fast asleep, Andrew Strangeway cycles silently over Westminster Bridge, bearing the weight of responsibility for a 165 year old national timepiece. He serves as guardian of a clock that has taken centre stage during coronations, commemorations, and countless moments of British history.

We meet Andrew Strangeway - the clock mechanic of Big Ben.

We'll all get an extra hour of sleep when the clocks go back on the last Sunday of October. That'll be Sunday, October 26; which will be one of Andrew's most hectic days at work. It falls to the 38 year old to adjust the capital's timekeeping across hundreds of clocks throughout the Palace of Westminster and ensure they chime precisely on schedule.

Andrew typically begins his day before 7am, traversing an unusually peaceful Westminster Bridge on his bicycle as gentle dawn light illuminates the Palace. Whilst others marvel at The Great Clock, Andrew ascends all 334 steps.

"There is definitely pressure for sure," Andrew confessed as we strolled around the Palace of Westminster. "Especially on specific days. Remembrance Sunday - you've got to get that right. New Year's Eve... quite a lot of people watching that one, just a few million."

It's not just The Great Clock that depends on Andrew to keep ticking through the years; a vast collection of 300 heritage timepieces scattered throughout the Palace of Westminster also relies on him.

They maintain time in rooms you'd likely recognise from the news, such as the 1922 committee room.

"The clocks going forward is big day and it's going to be a long weekend. We're in Saturday and Sunday because as well as these 300 heritage clocks there are also something to the order of two or 3,000 other quartz clocks and centralised systems, all of which need changing."

All of these require manual adjustment to the correct time - 3,300 in total.

Big Ben was fitted 165 years ago and has since marked British history. It has maintained time whilst coronations passed beneath, ticked silently behind enormous demonstrations, counted minutes during state funeral processions, chimed whilst we honour fallen soldiers and rang once more to herald new years.

Despite the demands, there are numerous tranquil moments, Andrew explained: "It is a privilege working here and getting to see all of the things we see. We get to go to the beautiful libraries and committee rooms. We get to see them in a way that others don't like at dawn. You have to remind yourself that what you're doing is really quite cool."

Andrew revealed the secret behind Big Ben's unique sound. "Big Ben is cracked," Andrew shared, "The original hammer was too heavy, and it cracked the bell in 1862. It was only on there for a year. It's part of what gives Big Ben it's tone. You hear a strike of Big Ben, and you know it's Big Ben.

"It's supposed to be an E natural, but it's a bit flat because of the crack."

Today, a small hole can be seen in the 13.5-tonne bell where engineers have carried out repairs. The original hammer, crafted from solid iron, is on display within the tower in a room as you ascend to the top.

Despite the thunderous sound of the ringing bell, Andrew's favourite spot in the tower isn't next to the giant bell, but in the pendulum box. "It's a quiet space, and you can just hear the ticking of the clock. It's small and enclosed and you can't hear any of the outside noise of traffic or anything."

But what drives Andrew?

Interestingly, Andrew wasn't always a clockmaker. He grew up in Milton Keynes, relocated to London in 2009 and pursued a career as a mathematician.

He then spent three years teaching maths at a secondary school in Highgate. "but by the end, I realised teaching wasn't really for me," Andrew reflected.

"So then I retrained. When I was doing my postgrad, I thought I would do something more practical, something more hands-on and I've always liked mechanical things - fixing things, taking them apart, all that kind of business."

He embarked on an apprenticeship in 2018 and worked at a clock shop in Putney until August 2023, when he secured the role at the Palace of Westminster.

Over his year and a half tenure with The Great Clock, Andrew has discovered it seems to possess its own unique character. He shared: "It's a fantastic clock to work on and to get to spend so much time with one clock is actually a real privilege because you get to know all of its quirks.

"You kind of get a feel for how you expect it to run in certain conditions, and it throws you a curveball and its different to what you expect it to be."

As a mathematician, Andrew admits he has a "fixation or an obsession about timekeeping", and the challenge of perfecting it is one of his favourite aspects of the job. This New Year, under pressure, he revealed he managed to have Big Ben chime in the New Year within 0.005 seconds of the exact time.

The weather plays a significant role in his job as it can influence the clock's mechanical timekeeping. To counter this, "you need to change the speed of the clock so it reaches the correct time."

Oddly enough, this is achieved by placing old Victorian pennies on a small shelf on the pendulum.

"Placing the pennies part way up the pendulum essentially raises the pendulum's centre of gravity so it will swing slightly faster."

This tradition started in the 1930s, Andrew reckons, when an old clock mechanic forgot the usual weights down the 340 steps at the bottom of the tower and used pocket change instead. Who can blame them for wanting to avoid this massive climb?

For more photos of Andrew and his work on Big Ben see below:.

To adjust the clock for British Summer Time, Andrew will have to tweak the 'gravity legs' above the pendulum which prevent the clock from just spinning out of control and dropping the weights down the tower. Pulling the legs apart in a controlled manner will spin it to the new correct time.

These gravity legs are one of many technological advancements that The Great Clock introduced when it was built that make it an excellent timekeeper. Clocks before it were roughly accurate within a minute; Big Ben "was designed to strike within one second of the correct time", Andrew stated.

The clock also has a unique electric winding machine to wind 2.5 tons of weight, which powers the clock. It had to be reverse-engineered from scratch for restoration after the company that built it in 1914 left no instructions behind.

Nowadays, modern technology is used alongside mechanics, with various electrical monitors in place and the use of highly accurate GPS clocks to set the time.

A common misconception is referring to the entire tower as Big Ben, when in fact, that's just the name of the bell. Andrew clarified: "So it's The Great Clock inside the Elizabeth Tower that rings Big Ben."

When questioned if this common error irks him, Andrew responded: "No, not at all. I'm probably a pedant by nature, but over time, I've just mellowed," confessing that he and his team often call it Big Ben too.

Despite the thrill of being up in the tower, much of Andrew's time is actually spent in the basement workshop of the Palace. Here, after a daily winding round of some of the 300 clocks around the Palace, Andrew busies himself with his craft.

"It's quite creative. That's what's appealing about clockmaking; it's the making," he expressed while showing off a custom tool he had fashioned to repair a tiny cog in a 200 year old clock. These clocks each have their own personalities, with past clockmakers leaving their mark by engraving their initials on them after services and peculiar design choices like using Fs instead of Xs for the Roman numeral 10 - a design decision by Palace architect Augustus Pugin, Andrew explained.