Dublin to Belfast Coast

Sprawling out from the River Liffey,

Dublin is home to more than a million people.

That's over a quarter of the Republic's total population.

It was the Liffey and its link to the open sea that brought Dublin its prosperity.

This is Dublin's Great South Wall,

built nearly 300 years ago

to protect ships sailing into the River Liffey.

On the far side of the estuary is the Bull Wall, added a century later

and designed to stop the sands of Dublin Bay choking the river.

Almost two-thirds of the Republic of Ireland's sea trade moves through Dublin.

These two massive walls are still vital in keeping the seaway open.

Between them, the deep shipping channel remains open at all tides,

while the beaches on either side are dried out twice a day.

The sands stretch the full sweep of Dublin Bay.

I'd never been here before,

but Dublin writer Fionn Davenport revels in his city's secret riviera.

I never pictured Dublin like this, with a great huge beach.

15 miles of beaches stretching from the north, down to the very south.

It's great, isn't it?

I'm ashamed to say that when I hear the word "Dublin", I just think, you know, pubs and pints and Guinness.

This is exactly how we sell ourselves. This is the great secret of Dublin - our beaches.

We don't talk about them, don't tell anybody about them,

and we keep them exactly the way we want them - empty.

The Irish are known for their hospitality, whether their visitors are invited or not.

Nowhere more so than Dublin.

In fact, historically, this city has scarcely been Irish at all.

The history of Dublin is the history of invaders.

Right from the very, very start, it was created by invaders,

populated by invaders, so in a sense, Dublin is an invader city.

Who were the first people to settle here?

Oh, the Vikings, in the 9th century.

They came here on their raping, pillaging, warring ways,

and they settled, and built this trading port.

The name Dublin comes from the Irish "Dubh Linn",

and the original Viking settlement was built around this black pool.

-That's where the word comes from - "dubh" meaning black, "linn", the pool.

-Blackpool?

-Yes.

-I was hoping for something Gaelic and lyrical like "shining city by the sea."

-I know.

A Viking Blackpool - that's a scary thought.

Then, in the 1100s,

another wave of invaders flooded up the Liffey - the Normans.

They and their English successors would stick around for 800 years,

long enough to make a mark.

Dublin's best-known brewery, Guinness,

was founded by an Anglo-Norman family,

and Dublin architecture still reflects the longstanding link across the water.

In Ireland's capital city, what is Britannia doing on top of that building?

Ah, Neil, because secretly, Dublin is still a little bit British. It's a very English city.

800-odd years of English rule -

Dublin was created, conceived of, developed and built by the English,

and this building behind us is the Custom House,

which was built when this was the second city of the British Empire.

I would have to dispute that as a Scot. We were always told Glasgow was the second city of the Empire.

But the tragedy of the Scots is they were lied to for so long,

because Dublin was the second city of the Empire.

Today, Dublin takes second place to no-one.

Glass and steel has transformed the old waterfront.

It's Dubliners who are flooding to the Liffey now.

The quickest way out of Dublin isn't by boat

but by DART, the fast rail corridor that hugs the shoreline of Dublin Bay.

The DART has made these once sleepy coastal suburbs

much more accessible to commuters, but ironically,

locals will tell you that today owning a seafront property

is beyond the reach of most Dubliners.

Unlike Britain, Ireland gives artists and entertainers generous tax breaks.

For these glitterati, Howth Head has become an exclusive address,

with properties changing hands for over £5m.

I'm Dave Kelly, and I sell spectacular seaside homes to the rich and famous.

Welcome to one of Ireland's most exclusive residential addresses - Sutton Castle.

This house was commissioned in the 1890s by the grandson of John Jameson of the famous Irish whiskey brand,

and it's recently been converted into luxury apartments.

It's as close to the sea as you can get without getting your feet wet.

A sea view can easily add tens of thousands of Euros to the value of a property.

And for an apartment in this particular complex,

it can set you back anything up to 3 million euros, or 2 million sterling.

We've reached the River Boyne -

not just a waterway, more an artery leading to the ancient heart of Ireland.

It's so peaceful here today.

There's just me and some day-trippers, and the only sounds are from the sea.

It's hard to believe that so much of Ireland's history has happened around this one river.

For 5,000 years, since the first Neolithic farmers,

the mouth of the Boyne has been the gateway to Ireland's fertile heartland.

It's been navigated by Celtic traders, Viking raiders and Norman invaders.

Striding north, the flat coastal plains of the Irish midlands

give way to the mountains of Northern Ireland.

But in this border country,

a landscape much older than any national frontier divides Ireland.

60 million years ago, as the dinosaurs were dying out,

the Earth's crust stretched and fractured here.

Explosive volcanoes erupted, and mountains were thrown skywards.

Its legacy is the rugged shoreline around Carlingford Lough.

On the far side of the lough is Northern Ireland,

but I'm still in the south, and it's a Euro zone.

But this close to the border, the Euro and sterling co-exist,

and for a few, that presents a lucrative opportunity

to exploit the difference.

Why's it so busy?

-Well, I suppose because it's cheaper.

-How much cheaper?

Er... Approximately 20% cheaper on both petrol and diesel.

So if you were filling up a typical car, what's the saving?

Approximately £12 sterling.

-That's a brilliant saving.

-Yep.

Where exactly is the border?

-I challenge you to find it.

-You're on!

And he was right - despite having different capitals, different laws and different currencies,

the border between North and South has vanished altogether.

The first sign that you're in the North is the one in miles per hour.

Nature makes a better fist of a frontier.

The massive granite buttress of the Mourne Mountains is a formidable obstacle.

Last time, we came here to discover how Belfast built Titanic.

This time, we're on a mission to uncover who built Belfast.

Belfast is the most industrial city in Ireland.

It defies nature that it's here at all.

Like Dublin, Belfast grew up around a tidal river -

the Lagan.

The original site was a ford, just where the river is spanned by these bridges.

Close by, they're building a 29-storey skyscraper.

Drilling for the foundations reveals just how much of Belfast

is built on mud and salt water.

That's the stuff they call sleetch!

I think you and I would call it filthy stinking muck.

In a funny way, it smells a bit like the sea.

It's got that pungent smell about it, like seaweed,

but seaweed that's been trapped underground for a long, long time.

But the point is, all of Belfast is built on top of that.

Kerry Greeves, the project engineer, is tackling the same problems as Belfast's original builders.

-The bedrock, which is sandstone, is about 50 metres down.

-50?

-Yes.

We have to use piles, which are going down on this side

approximately 28 metres, and that's what will hold up the building.

So the piles don't reach the rock?

-No.

-So the building is just floating on...mud?

Well, you could say that.

As an engineer, it's slightly more technical than that, but effectively yes.

Belfast's founding fathers floated their dream here on the shoreline.

Local author Glenn Patterson has summed up their achievement with these lines.

"Belfast is a triumph over mud and water,

"the dream of successive generations of merchants, engineers and entrepreneurs,

"their names driven like screw piles into the city's sense of itself.

"Dargan, Dunbar, Workman, Harland..."

The thing is, they're all Scottish or English names,

Protestant merchants attracted here from the beginning of the 17th century

by the promise of land at the water's edge.

I wanted to hear more from the man who celebrated these entrepreneurs.

A lot of people came here with ideas about settling this place, developing this place.

Some bloody-minded people, you would have to say.

This isn't a promising place to make a city.

Belfast has no business being here at all.

So what was behind the stubbornness?

Something must have attracted them and made them stay.

Belfast, although it's very unpromising, it's got all that muck, that sleetch,

you had to dig right down and sink your foundations if you wanted to build here,

you could actually make bricks out of the clay of the city,

so, in a sense, Belfast is a city that's made of itself.

Every inch of Belfast's industrial heartland is man-made,

dredged and reclaimed from the salt-water shore in the 19th century

to underpin its expansion.

But to build on that growth, Belfast had to look seawards again - to trade.

When you look at this vast port, it's almost as though this water matters more than the land.

Well, certainly without this, without the trade -

I mean we're sailing past these container ships here -

without that, Belfast wouldn't have developed in the way that it did,

and without the port, there wouldn't have been any of those great industries of the 19th century.

So this city really is defined by this water.

Belfast, the floating city.

Subtitles by Red Bee Media Ltd