[ Chimes ] -The Elizabeth Tower, known across the world as Big Ben.

[ Chimes ] ♪♪ It’s a British icon, but for five years, it’s been shrouded in scaffolding, dismantled piece by piece, and sent off to master craftspeople across the country.

-Let's see if I can snap it.

Oh, yeah.

-Their challenge?

Not just to maintain and preserve the tower, but to discover just how Big Ben would have looked when it was first built... Oh, my goodness!

That’s completely extraordinary.

That’s completely different.

...and re-create it with all its stunning colors and golden shine.

It’s been quite a journey.

-I think we’re actually losing something today, and I don’t think we’re going to really appreciate that until the next hour.

-From the very beginning, there’s been controversy... -It can’t be right for Big Ben to be silent for four years.

-...frustrations... -For 15 weeks, we weren’t doing any physical work on the site.

So, you can imagine if the site shuts for 15 weeks, then that just all -- everything just shifts over.

-...and obstacles to overcome.

-The minute hand is so tight on this center shaft, we’re having to use this puller.

-Now, at last, the works are complete, and Big Ben will once again ring out every 15 minutes for decades to come.

♪♪ I’m Dr. Anna Keay, director of the Landmark Trust.

And this is the story of one of the most ambitious restoration projects the world has ever seen.

♪♪ ♪♪ It’s December 2016, and with just one week to go before work begins, I’m about to get my first look inside the tower.

Hi.

-Anna, hello.

-Nice to meet you.

-A very warm, warm welcome to the Houses of Parliament.

-My guide is Adam Watrobski, Parliament’s principal architect and a driving force behind Project Big Ben.

The Elizabeth Tower, as it’s officially called, is 96 meters high.

-Just passing the entrance to the dials.

-The only way up is to climb 334 steps.

-That’s the clock mechanism room.

And this is it.

We’re just coming to the end now.

Another 20 steps or so.

-Oh, my goodness!

-And here we are in the belfry.

-Oh, my goodness.

It’s absolutely amazing up here.

-That’s right.

-It’s like being on top of the Eiffel Tower or something.

It's so much metalwork, isn’t there?

-A huge amount.

This is the bell frame, of course.

And right in the middle is Big Ben.

And this bell doesn’t swing.

It hangs there.

And then the hammer hits it, as you can see.

[ Bells ring ] -Oh!

[ Laughs ] [ Ringing continues ] [ Chimes ] Big Ben is the name of the Great Bell, but today it’s used colloquially for the whole clock tower.

It rings out at 118 decibels, almost as loud as a jet taking off.

-And that’s it.

The reverberation's huge.

-...are incredible.

-Yes, this goes on for quite some time.

-It’s like being in some amazing sound installation.

-Yeah.

-The thing that, of course, is so extraordinary is that this is all the original stuff.

But, also, I guess that is the massive challenge of this place, because it comes with having to maintain it.

-It does.

But then that’s what building conservation is about, isn’t it?

It’s about staving off decay.

-Yeah.

And you can see some quite serious issues -- can't you?

-- with the condition of the metal.

-Yes, this is a good example.

You can see quite clearly the water’s getting behind it, and the ironwork is beginning to rust.

-Pollution and the elements have been attacking Big Ben for decades.

Rain has forced cracks in the masonry, rust in the ironwork, and damaged the stone.

The cost of repairs are initially estimated at £29 million of public money.

It’s a huge undertaking, particularly as Big Ben is a Grade-1-listed building and a World Heritage Site.

The team must safeguard the tower’s exquisite details -- the winged gargoyles carved into the stone, the gilded orbs and crosses, and the Victorian ironwork laced across the clockfaces.

What the team are taking on here is eye-watering.

Big Ben is one of the most famous buildings in the entire world, and they are decapitating it and reconstructing it inside and out.

The top of the tower is going to be stripped down to its original frame... its giant hands, over 4 meters long, removed.

The four faces, each one large enough to drive a double-decker bus through, will be taken apart... ...and 2,567 cast-iron roof tiles and other parts restored.

♪♪ One of the world’s best-known buildings is about to become unrecognizable.

Work officially begins at Big Ben in the week before Christmas 2016.

Twenty removal men have arrived to clear out the clocktower.

They’re quickly discovering that there’s more to Big Ben than meets the eye.

The tower has 11 floors that few get to see.

There’s old parliamentary offices, a workshop, and even a Victorian prison, once used to lock up unruly MPs.

On the tenth floor is the mechanism room, and surrounding it are four giant clockfaces.

And at the top are the bells.

♪♪ -Right in here, we’ve got some historic tools, okay?

It is quite fragile, obviously, with the glass.

-This morning, all the action is on the seventh floor with Amanda, one of Big Ben’s longest-serving employees.

Amanda usually organizes small public tours of Big Ben, so today’s guests are a little different.

-Let's go.

Let's go.

-She has to make sure they carry every object out of the tower without damaging a thing.

Every item carried out requires a round trip of 700 steps.

This is not your usual two up, two down.

-[ Sighs ] -If we go for the chairs now, please, that would be great.

A chair each -- careful as you’re going down.

-Amanda has worked at Big Ben since leaving school.

-It is time for me to leave the tower and pack up.

[ Bang ] There we go.

It’s going to go.

[ Clanging ] I’m going to miss that.

I’m going to miss that.

I’m really going to miss being up here.

So, I’ve brought so many people up the clock tower and shown them around.

And I love watching people’s faces light up.

I think it’s because it’s witnessed so many great things.

It’s part of our heritage.

It’s so strong and steady.

It’s a symbol of our democracy.

And that, I think, in the 21st century, is a nice thing to be proud of.

-Big Ben was built after fire devastated the old Houses of Parliament in 1834.

Since then, its four great clockfaces have watched over 7 monarchs, welcomed in 32 prime ministers, and survived 2 world wars.

And throughout it all, Big Ben has rung in over 160 new years.

♪♪ [ Camera shutter clicks ] Big Ben is one of the most photographed buildings in the world.

-Say cheese.

-It’s magical.

-Yeah!

-It’s better than I ever imagined.

It’s amazing.

-I love you.

You’re perfect!

♪♪ -But for the next five years, it will be encased in scaffolding.

This alone is a monumental task.

The clock tower is almost 100 meters high and will take the best part of a year to cover.

In what ways do you think that despite the fact that Big Ben is going to be covered in scaffolding, that it’s still going to be able to sort of play its, you know... -Play it’s part.

-...icon-of-the-nation job?

-Yeah, well, I think visitors to the Westminster area are going to... It’s going to be a shock for them, but it’s got to be done.

So, we want to preserve it for future generations.

And the way we’re going to do that is to obviously do this work.

We won’t cover all the actual dials' faces all at the same time.

So, something will always be displayed, which is really good.

Obviously, we’ll keep chiming for as long as we possibly can.

-But Big Ben’s chimes are silenced much sooner than anyone is expecting.

-On Monday, the parliamentary authorities announced plans to silence Big Ben for four years.

-Four years?!

-Yeah.

-No, I didn’t know this.

-I think we’re actually losing something today, and I don’t think we’re going to really appreciate that until the next hour, when there’ll be silence.

-It can’t be right for Big Ben to be silent for four years.

-The uproar is much more than anyone anticipated.

Yet Parliament presses on with plans to silence the bells, largely to protect the hearing of the workers on the scaffolding.

[ Chimes ] Now Big Ben will only be heard on special occasions, such as Remembrance Sunday and New Year’s Eve, when it will be powered by a temporary electric motor.

The task of disconnecting the bell falls to one of Parliament’s in-house clockmakers -- Paul.

It’s a big day, isn’t it?

-It is a big day, yeah, yeah.

-I mean, it’s been amazing how much there’s been in the press, and I guess that in part must be a reflection of the fact that people do really care about it.

-Yeah.

I mean, I think probably people underestimated how much, you know, it has meant to various people.

-It is an expression of how much it matters and... -It is.

It is, yeah.

-...sort of, of love, really.

[ Bells ring ] It’s nearly 12:00 when Big Ben’s bells will chime for their final time.

[ Ringing continues ] The clock will now be silenced for the longest period in its history.

[ Chimes ] [ Chimes ] [ Chimes ] [ Chimes ] [ Chimes ] [ Cheers and applause ] Oh, can you hear them?

-Mm-hmm.

-Oh, my goodness.

Did you know that was going to happen?

-It’s surprising how many people decided to come.

-It’s just the beginning.

That’s the funny thing, isn’t it?

-It is the beginning.

-There’s no turning back now, is there?

-No.

♪♪ -For a year, around a hundred specialists have been working flat-out on the Elizabeth Tower, more commonly known as Big Ben, putting up over 96,000 pieces of scaffolding.

♪♪ Now, in February 2018, work can begin with the removal of the tower’s most precious asset -- the Great Clock.

And there are three men who know how to do this -- Parliament’s clockmakers.

-It's gonna take the strain.

-Ready, chaps?

-The first thing Huw, Paul, and Ian have to do is remove the hands.

-I’ve been working here for 14, 15 years now, and this is the first opportunity to actually get my hands on the clock hands.

We can’t do anything on the inside until we’ve taken the hands off.

So, it’s just a big, significant part of the work.

Take the hands off, and it’s no longer a clock.

-[ Groans ] -The minute hand is so tight on this center shaft, we’re having to use this puller.

So, hopefully, we can get this on the back of the minute hand, through this bolt up onto the arbor in the middle, and hopefully that will draw it off.

Obviously, it’s been on there for a long while, and it’s just a bit seized on.

-Has it started to...?

-Yeah, yeah.

-There you go.

So, that’s actually broken the stickiness on it.

And now the hand will slide off, hopefully.

-So, we want get this puller off now, don’t we?

-All right.

Ready?

Okay.

-Good job, Huw.

-The 14-foot minute hand will be lowered 25 floors to the ground.

-Side on, lad, side on.

-It’s strange to see it off the clock, isn’t it?

-Seriously, it’s dead now.

-If you think it looks dead now, you wait till we lift it into its coffin.

[ Laughs ] -The team spend two days on the clockfaces, removing the hands and packing them away.

-Everybody breathe a sigh of relief.

-But the clockmakers' biggest challenge is still to come -- dismantling the enormous mechanism that lies hidden behind the clockfaces.

This intricate machine has kept Big Ben’s clock ticking almost continuously since it was first assembled in the 1850s.

The clock is powered entirely by gravity.

Three weights hang below the mechanism, moving up and down a shaft in the center of the tower.

As the weights drop, they provide the power to drive the clock and ring the bell of Big Ben and its four quarter-bells.

[ Bells ring ] [ Ringing ] ♪♪ Astonishingly, the clock is kept precisely on time with the help of a pile of pennies balanced on the pendulum.

Adding or removing a penny varies the time by two-fifths of a second a day.

Now, with no instruction booklet to guide them, the clockmakers must break down the 11.5-ton mechanism into more than 1,000 different elements and lower them to the ground 55 meters down the weight shaft.

-This is probably the first time these parts have ever left this room, you know?

So, it’s kind of sad, almost, seeing it all leave the room.

-The Great Clock’s entire mechanism is going to an off-site workshop for the first time in its history.

Here, the clockmakers will examine every cog, wheel, and screw to ensure it will ring for another 160 years.

It’s not just the clock that’s being broken down and removed from the tower.

Almost every piece of the ornate roof is being dismantled and taken away for repair.

At the top of the tower, the cast-iron roof, all 3,500 pieces of it, has now gone.

What’s left is the original frame.

Crikey.

It looks all naked, doesn’t it?

They’ve all come off.

-It is.

It’s completely.

And it’s surprisingly modern, isn’t it?

-At every level, Big Ben seems to be disappearing before my eyes.

What has actually happened here so far?

-Everything that can be stripped off has been stripped off and is being stripped off at the moment.

This will come off.

-It’s like a giant Meccano set, isn’t it, with the bits all being unbolted?

-It's a giant Meccano set, yes.

-These bolts, which have just been extracted here, have those ever been unscrewed before?

I mean, since they were put in place?

-No.

-No?

Never?

-Not to the best of my knowledge has never, ever come off.

Really, the problems have arisen with postwar repairs.

-Yeah.

-There’s the bomb damage, of course, on the south elevation, which faces back towards Parliament, where the bomb fell in 1941, which actually damaged quite considerably the south elevation of the tower, which is where we’re standing now.

[ Bells ring ] -There’s the wail of the banshee.

-On the 10th of May 1941, the Luftwaffe destroyed the Commons chamber, set fire to the medieval roof of Westminster Hall, and hit the clock tower.

The glass on the south clockface was shattered and the tower blackened and scarred.

♪♪ Yet, miraculously, the clock and bells were left unscathed, allowing Big Ben to ring out defiantly for almost the whole of the war.

♪♪ Today, I’m in Sheffield, where the metalwork stripped from Big Ben has been sent for restoration.

The project is being run by Trevor Marrs, and it looks like he’s got his work cut out.

-Right.

So, this is where you’ve got all the Elizabeth Tower components.

So, we’ve got the work bays over to the right and the components waiting to go across to be worked on.

-Absolutely massive place.

Is it all...?

It's all Big Ben here, is it?

-All of it, yes.

Everything.

-Wow.

Yeah, wonderful as I recognize these lovely balustrades.

-Yeah, so, these are the balustrade sections that we’ve got and wrought-iron sections.

-They look like bits of a body, don’t they?

-[ Laughs ] -Sort of thing.

Sort of weird how confusing it is when it's taken to pieces.

-Has been referred to as an elephant’s graveyard almost, isn’t it?

-It looks like that.

It looks ilke that.

Exactly.

If you saw all of this and said, "If you put all this together, what would it make?"

you’d never come up with Big Ben.

-Well, hopefully, it will all go back together again.

Overall, in here, in the Elizabeth Tower, we’ve got 3,222 components.

-Before workers here can investigate the state of each piece, everything must be stripped down to its original metalwork, either by sandblasting or with chemicals.

Only then can any issues be spotted and repaired, before it’s sprayed with zinc, to stop any future rusting, and repainted.

Of the sort of 3,000-odd, how many of those elements, roughly, are you having to do something quite serious to?

What proportion?

-I would say virtually everything.

-Really?

Really?

-Everything, every single element that’s come into here has needed a fairly significant amount of work.

-What really blows your mind coming here is that it’s sort of about scale.

Though there’ve been many campaigns of repair on Big Ben before, but in every one of those cases it was done on-site.

What’s never happened before is what this all is, which is to say Big Ben, basically, being taken to pieces and taken off-site and worked on individual element by individual element.

The extent to which really beautiful, proper, comprehensive repairs are being done now is without precedent on this building.

So, lots of the other mends have been literally that -- mends -- whereas this is really properly about repairing and conserving the whole structure.

♪♪ -How are we going to get this out?

-Thirty miles away, at the Hargreaves Foundry in Halifax, Michael Hinchliffe and his team are casting new ironwork for the tower.

-When we’re making the castings for the Palace of Westminster, we do take the scrap tiles, or scrap cast... -Oh, these are the original -- these bits are the original tiles off the roof.

-Yeah, absolutely.

-So, the ones that are too damaged to be just repaired and put back can then be made into... -Into the new ones.

-...to the new ones.

-Yeah.

Yeah.

-Today, Michael is making a decorative buttress to replace a damaged one from the roof of Big Ben.

And to produce the molten iron, scrap metal is melted in a blisteringly hot furnace.

[ Sizzling ] Oh!

-So, that raw material now has come through this furnace.

-So, here’s our molten... -Yeah, molten brick.

There's molten bits of the tiles from the Big Ben tower, and then that is molten cast iron at 1,500 degrees centigrade.

-Any impurities in the cast iron are easily removed as they all float to the surface.

-So, this is the mold for the buttress, and this is the metal going in there.

So, at this moment now is the time when the actual buttress is being created.

[ Sizzling ] -Aah!

It’s quite tricky because it’s a really small hole -- isn't it?

-- that you have to pour it into.

-Yeah.

-So, now it’s all in all those little crockets and things.

-That's it.

So, that... Yeah, it’s gone through everywhere now.

That mold cavity is now full of iron.

So, it’s created.

-You feel the heat, don't you?

-Yeah, yeah.

So, this metal now is starting to solidify.

In a few hours’ time, it will be maybe down to 400 or 500 degrees.

And, actually, at that time, we could lift it out of the mold.

-The foundry was started by Ebenezer Hargreaves over 140 years ago, and the casting process has barely changed since.

-The guys that made the casting for Big Ben originally would recognize this and fit in with us easily, very easily.

You know, we have a connection with them.

We know, I know what their lives were like.

♪♪ Having the accolade of being trusted to work on Big Ben is like the pinnacle of all our careers, actually.

Yep.

Looks good to me.

-It looks pretty good to me.

Back in London, work continues on the clock tower’s stripped-down frame.

Restorers are busy scraping away thick layers of paint -- a century and a half’s worth.

It’s the perfect chance to discover the original colors of Big Ben.

Hi, Mark.

Nice to see you.

-Hello.

How are you?

-Yes, well, thanks.

Parliament’s historian Mark Collins knows that when the clock tower was first painted in the 1800s, it wasn’t the somber black we’re used to today.

-We’re keen to check the layers of paint so that we can go back to the original scheme.

-It’s a pretty labor-intensive process, isn’t it, just lifting off the paint layers?

-It is.

There are about 25 layers altogether.

It’s been overpainted... -Yes.

-...in fact, over the years, mostly with black paint.

So, the surfaces have been covered over because, of course, London’s atmosphere was very sooty.

It was very black.

And so this was...

This was the reason that any color was lost.

They just gave up on it, really, and used black paint instead.

-Yes.

With a team of conservators, Mark wants to strip away the black and find Big Ben’s first color scheme.

♪♪ So, they send the paint samples to the conservation department at the University of Lincoln.

Here, scientists put them under the microscope to discover just which colors the tower’s Victorian architects used.

I’m meeting Rhiannon Clarricoates, who’s an architectural paint researcher.

Hi, Rhiannon?

-Oh, hi.

-Hi.

I’m Anna.

Lovely to meet you.

This sample contains the first paint scheme from the clockface and hands.

And the $64 million question, for me, in your research is, you know, what was the color on that?

-Well, I think you’ll find that it’s changed quite significantly over time.

If you’d like to have a look down the microscope, you can see there are at least four schemes.

They’re quite markedly different.

Would you like to take a look?

-Thank you.

Yeah.

Oh, my goodness!

That’s completely extraordinary.

That’s completely different.

It’s blue.

It’s not black at all.

-Vibrant blue.

-Yeah, vibrant blue.

-And there’s been at least four sort of successive schemes of it being blue.

-So, it wasn’t just blue for kind of five minutes?

-No, it was it was blue right up until about the 1930s.

-It looks incredibly modern, actually, doesn’t it?

That is so exciting to think that that’s going to be recovered.

Oh, it’s absolutely gorgeous.

But this is just the beginning.

As the restoration continues, more of Big Ben’s secrets will be revealed.

♪♪ Restoring Big Ben is an ambitious project on a mammoth scale, including the budget, which by this stage has already more than doubled to £61 million after the true extent of the damage is uncovered.

With Big Ben shrouded in scaffolding, it’s difficult to see just how much progress has been made.

So, I’m with the project’s principal architect, Adam, who’s going to show me the most photographed part of Big Ben -- the clockface.

Aha.

-You can see... -Yes.

-...quite clearly this has been primed, of course, and repaired.

-Yeah.

-But this is the cast-iron frame.

-So, we’re at the six here, aren’t we?

-We're at six.

-The bottom of the dial.

-Yes, we’re right at the bottom of the dial here.

-And it’s naked.

It’s had all its old paint taken off.

-It’s had everything taken off.

And it’s had its new undercoat on.

-Yeah.

-And it now needs to be top-coated, two topcoats, of course, in the blue, but it needs to be glazed.

-Reglazing this clockface is no easy task.

-These amazingly thin glazing bars, which you can see, there’s practically no purchase there for the glass at all.

-Yeah.

-So, the glass cutting has to be extremely accurate in order to fit into that.

-Yeah.

-Each and every piece, of course, it has to be templated because they’re all different sizes... -Yes.

-...as you might imagine.

But quite an extraordinary job to glaze, actually.

-This tricky task belongs to leading stained-glass artist John Reyntiens.

For the last year, he has been hand-cutting mouth-blown pot-opal glass for the four great clockfaces.

-We’ve got about four or five mil to play around with.

Let’s see if I can snap it.

Oh, yeah.

A1.

-Today, John and his team are painstakingly fitting the freshly cut pieces into the north clockface.

-Okay.

Pushing out.

-John, it’s really interesting sitting here because, of course, it reminds you that the glass is offered up behind the clockface, isn’t it?

-Yeah.

-So, it isn’t necessarily obvious, if you don’t know, that each individual element here is a separate piece of glass rather than big, flat plates of glass being applied over the ribs from behind.

-Yeah.

And people do think it’s great, big pieces of glass.

-Yeah.

-And we have to explain, "No, it’s not.

It’s smaller sections."

-Each one of these...

I mean, that piece couldn’t go in there and that piece couldn’t go in there.

Each piece is specific to it.

-Every piece had to be templated individually.

-Yeah.

-So... And, actually, if you look at the templates, every template is a different size.

So, there’s not... You couldn’t suddenly use five of those in one place.

You have to template everything.

-It’s bespoke on a whole new level, isn’t it?

-Yeah, and what’s nice now, if a piece gets broken, we’ve got a template for it.

-As work progresses on restoring the famous clockfaces, I head to Penrith, to the Cumbria Clock Company, where the internal mechanism has been shipped, piece by piece.

Hi, you two.

-Hi, Anna.

-Hey.

-Crikey.

Well, things have moved on a bit here, haven’t they?

-They certainly have.

-Here, Ian, Huw, and the clock team are inspecting every cog, wheel, and screw.

Huw, I mean, this looks like it’s sort of, it’s all finished.

I mean, it’s looking absolutely beautiful, all these elements.

But I know that it isn’t.

So, what stage are we at?

-Right, the stage that we’re at at the moment is that we’ve actually now cleaned all the parts, and we’ve put a primer on to protect the surface of the metal.

-So, that’s the red color we see on here?

-Yes.

Yes, so, this isn’t the finished color.

-Which element are we looking at here of the clock itself?

-This is the north-dial motion work.

This is what actually drives the minute hand and the hour hand on the north dial.

[ Clicking ] -It’s a wonderful sound, isn’t it, hearing it going round?

-It’s nice when it’s nice and quiet.

If there’s clunks... -That’s when you would worry.

-Yeah.

-Yeah.

You know there’s something... Or God forbid if there’s any grinding.

-Grinding -- that’s what you really don’t want.

-Yeah, grinding’s not good.

-Before being reassembled, every part has to be deep-cleaned in pressurized water.

It’s only when 161 years of dirt is washed away that potential problems come to light.

-This is another piece, but a little bit of dirt or grease have actually got into this here.

If I... [ Grinding ] Yeah, we’re... [ Smooth scraping ] That’s the difference.

So... -Trapped dirt has worn down the spindle’s surface.

If left untreated, it could have had catastrophic consequences and stopped the clock.

-We couldn’t know about this because this is one of the parts that we can’t get to with easy access.

So, this is one of the important reasons why we have checked every single part.

-Fortunately, the damage has been caught in time and can now be repaired by the team.

In the spring of 2019, Project Big Ben reaches an exciting milestone.

And after more than two years of hard work, it’s time for the first section to be revealed -- the iconic north clockface.

This is the original color scheme.

Out, the brooding black on the dials... and in, a rich Prussian blue.

Out, the gloomy corners... and in, gleaming, gilded stone and bright cobalt blue.

Out, the patchy postwar glass, and in, mouth-blown, hand-cut replacements -- each piece bespoke.

Out, every inch of black paint.

Welcome to Big Ben’s stunning, new clockface.

It’s incredibly exciting to see all the hard work begin to pay off.

And just six months later, the next stage of the project is ready to be revealed.

Parliament’s principal architect, Adam, takes me up to the top of the tower to see the newly finished roof.

Oh, my goodness.

Look at that!

-This is the first bit to be completed.

-It’s like a rebirth, isn’t it?

Look at it.

-It is.

Isn’t it astounding?

-It is absolutely gobsmacking.

-If you start right at the top with the spray of flowers, of course, and the gilding and the auburn across, it’s just amazing, and the crown.

-Oh!

♪♪ Isn’t it extraordinary?

-It’s extraordinary, isn’t it?

-Yes.

Well, it's the light, the gold, and the gray, and then all these brilliant... -And it’s been very beautifully done, very beautifully done.

-...sort of symbols of nature.

But it’s also so wonderful, having seen various of these individual elements, like those little sort of details over the dormer windows, taken completely to pieces, absolutely disassembled... -Indeed.

-...and then all being put back magically together now.

It’s starting to feel as though the end is in sight.

Then, suddenly, work is brought to a shuddering halt.

-Good evening.

The coronavirus is the biggest threat this country has faced for decades, and this country is not alone.

All over the world, we’re seeing the devastating impact of this invisible... -In March 2020, the United Kingdom goes into lockdown.

Work at Big Ben grinds to a halt for more than three months.

These are testing times for the team.

And when workers return, they have to socially distance in a clocktower with a tiny footprint of only 12 meters square.

So, Nick, we’re standing about 200 feet up in the air, aren’t we, on this scaffolding that’s on the outside of Big Ben?

-We are, yes.

Yeah.

-And it’s a real reminder of just how challenging it must be for you and the gang here to operate a site with social distancing in the middle of a pandemic.

-It’s been a big challenge.

-What would you say the impact on this project will be?

-We were shut down for 15 weeks.

We weren’t doing any physical work on the site.

So, you can imagine if the site shuts for 15 weeks, then that just... Everything just shifts over by the equivalent amount.

But then going forward, we’ve obviously had to come back very, very slowly and incrementally, just to make sure we can manage it safely.

-Along with the extra challenges, the pandemic also added another £9 million to the budget.

The initial estimate of £29 million had by this stage more than tripled to a grand total of £88.7 million.

So, in the four months or so since the site reopened, what are the big things that have happened here?

-We’ve got a chance now to strike the scaffold at the top of the tower, which is another amazing milestone.

And we’re taking it down to the belfry level, which is obviously where Big Ben is.

So, it’s going to be quite a sight, and I’m really looking forward to seeing that myself.

♪♪ -Like a phoenix rising from the ashes, Big Ben’s sparkling, new exterior is slowly emerging from the scaffolding.

Historian Mark Collins was the driving force behind the return to the original paint colors, and today is his first chance to see them up close.

Mark, it’s such a thrill to see this clockface completely revealed today, isn’t it?

Is the overall impact of it, standing here, as you thought it would be?

-I think it’s better.

It’s got this... All the stonework is so much fresher now.

You haven’t got that black paint all over it that had been put there nearly a hundred years ago.

And, of course, it’s much cleaner stone all the way around, and the color makes all the detail stand out more.

-It’s just got such a wonderful sense of celebration about it.

-I think there is a bit of element of surprise, which I quite like, actually, because it shows that the Victorians weren’t quite so black and white.

♪♪ -From the outside, it might seem like the Big Ben renovation is nearly complete.

But there’s still the small matter of returning the enormous clock mechanism to its home on the tenth floor.

Turret-clock specialists Keith and Mark have been working alongside Parliament’s clockmakers.

Putting more than a thousand Victorian clock parts back together in the correct order has been quite the challenge.

I didn’t realize quite how much had gone back in.

This is amazing.

-It is, isn’t it?

I mean, it’s been a bit of an adventure and a little heavy lifting.

-Reassembling the clock is far from the end of the process.

It will take months of testing to make sure it’s running exactly to time.

-The next step at the moment is testing the bells so we can all hear the familiar sounds of Big Ben striking again, which a lot of us have missed.

-I think the thing which is going to surprise people is that the chimes are going to sound different, because we got used to that kind of staggering quarter-chimes.

It’s like... bom...bom-bom-bom.

But it’s going to be a lot more precise, because we’ve made everything work better.

Literally -- bom-bom-bom-bom-bom-bom.

So, it’s going to change.

And, you know, in a way, I think that’s brilliant.

As much as we’ve discovered the blue dials, rediscovered the blue dials, perhaps we’ve rediscovered the proper quarter-chimes.

-With the restored clock back in place, it can now take over from the electric mechanism to power the bells once more.

The team take me up to the little-known link room, where they are finessing the bell sound.

We’re directly over the clock mechanism.

-It’s directly above the clock, between the clock and the bells.

-Those famous chimes are played by the four quarter-bells.

Big Ben itself then strikes the hour.

So, if you tug on that, what happens?

-Yeah.

Do you want me to?

-Go on, then.

-Okay.

Whisk it up.

-Oh, gosh -- heavy.

[ Chimes ] This shows with the heft of this machine, though, doesn’t it?

-Yeah.

♪♪ ♪♪ -I’ve been following the project to restore Big Ben for six years now.

And today, finally, I’m going to have the chance to see and hear the finished result.

It’s a project that everybody can be incredibly proud of.

♪♪ It’s Remembrance Sunday, and the day has finally come for us to see if the 6 years of hard work from over 500 people -- and an estimated £88.7 million -- has paid off.

I’m heading to find out if Big Ben is ready for its big moment.

♪♪ Hi.

Lovely to see you all.

-Hi.

-Hey.

Welcome.

-She’s looking amazing, isn’t she?

-Thank you.

-Each of the individual elements reassembled, and with the original paint colors, is that right?

-It’s the original paint colors.

-What about the famous pennies on the pendulum?

-They’re back.

-They’re still there.

-Yep.

We’ve put on the original timing weights, which look like a penny with a little stalk on it.

-Oh, yeah.

-And we’ve got the pennies.

-It’s amazing how many people actually send us pennies in... -[ Laughing ] Oh, do they?

-...so they can say that their penny has actually gone on the... Yeah.

-Well, that’s a lovely thing, isn’t it, that people know that and there's an association... -And we’ve probably got enough pennies now to last another 160 years.

-Yeah.

-And does it feel to you like it’s absolutely still the same, or does it feel like it’s a different generation somehow?

-Well, it’ll sound a little bit clearer, and it should be how it was when it came out originally, 160 years ago.

-After five years, the original clock mechanism has been reinstated.

Four quarter-bells are set to finally resume ringing out over the capital every 15 minutes.

And we’ll get to hear Big Ben just as the Victorians would have.

So, today’s the day, isn’t it?

Remembrance Sunday.

It is the launch of the restored Big Ben.

-Hopefully everybody will appreciate the sound being back after the five years.

-You’ll hear it.

Everyone else will hear it.

Big Ben is back.

-With just minutes to go, I’m heading to the belfry, where I’ve got the best seat in the house.

[ Ringing ] [ Ringing continues ] [ Chimes ] [ Chimes ] [ Chimes ] [ Chimes ] [ Chimes ] [ Chimes ] ♪♪ It’s been so uplifting to see this project finally come to completion, to see Big Ben restored, but also to hear it, to hear the sounds again of the bell being struck on the hour and for Remembrance Day.

This building -- always a monument to Victorian engineering and confidence -- is also now a monument to all of the people who worked on this project, across a huge range of different disciplines, from stonemasons to glaziers to the clockmakers themselves, through the engineers, the project managers, everybody.

Big Ben has been hidden these last six years.

It’s been behind hoardings, closed up.

And it’s been a kind of unnerving feeling to see it like that, not least because these have been very difficult years.

So, there’s something about seeing it revealed today and renewed that gives you hope, gives you a sense that just as Big Ben has lived through war and crisis before, it will ring on.

♪♪ ♪♪ ♪♪ ♪♪