Scottish independence: What would it mean for the NE and Cumbria?
It is less than six months until the people of Scotland go to the polls on the issue of independence. If they vote "Yes", England's North East region would have an international border.
Political correspondent Mark Denten travelled to the Irish border to see if there are any lessons to be learned.
I'm driving along a country road. The scenery is pretty but otherwise it is unremarkable.
However, I'm actually also driving across an international border.
Just outside the Northern Irish town of Newry, I've crossed - almost without knowing it - into the Irish Republic.
These days, only the road signs in kilometres give you a clue that you are in a different nation.
It is a far cry from the years of The Troubles when this would have been an area of Army checkpoints - not exactly the place for a quiet spin in the countryside.
With Scotland's independence vote happening in less than six months, there could be an international border in the North East and Cumbria.
So are there any lessons to learn here?
I meet the Doyle family shopping for clothes in the Northern Irish border town of Enniskillen.
Mick Doyle is originally from Hebburn, in South Tyneside, but has lived in Ulster for a decade.
He routinely carries both Euros and pounds in his wallet.
"When you come into a shop you'd get the Sterling price and you would also get a Euros price on the goods.
"You can pay for that in Sterling, in Euros or you can pay in a mix of both."
Supporters of Scottish independence say this sort of situation would not arise on the English-Scottish border because Scotland would keep the pound.
The UK government - equally adamantly - says that is not going to happen.
But Mr Doyle believes if Scotland did have a different currency, the North East and Cumbria could cash in.
He tells me it has certainly happened here.
"Enniskillen has benefitted greatly from having the border very close because when the exchange rate is the right way around it can draw a lot of people across the border to spend a lot of money.
"They're coming across to do the family shop.
"If [places such as Carlisle and Berwick] set themselves up and they adapt themselves and get ready for business to come across the border, when the exchange rate is the right way around they've got a great opportunity."
Sixty miles to the south east, I pass a road sign saying 'Welcome to Newcastle'.
This place has no quayside, but a seaside complete with the Mountains of Mourne sweeping down to it - just like it says in the famous song.
We are still in Northern Ireland - again not far from the border with the Republic - but watch repairer Peter Lord might as well be hundreds of miles away.
He says his example should be a cautionary tale for North East and Cumbrian businesses as dealing with a separate country can be costly.
He does most of his mail order business with Scotland and the rest of the UK but hardly any with the country just up the road.
"There's an awful lot of trouble getting Euros converted. Even though it is only 100 miles to Dublin it is treated as international and therefore it's very hard to get your parcels insured.
"It would cost seven or eights pounds to send an average parcel to Scotland, it would be considerably more expensive if I was to send exactly the same thing to Dublin."
But Thomas McGowan, the chief executive of InterTradeIreland - an organisation set up to foster cross-border trade - says businesses in the north and south are now frequently working together after they had "turned their their backs on each other" during The Troubles.
Mr McGowan tells me that trade now generates around 1,000 jobs every year.
With no such recent history of conflict, he says an independent Scotland could be a potential plus for the North East and Cumbria.
"My advice to the people in the North East and Cumbria is not to fear this border.
"There's good trade happening between companies in the North East and Cumbria with Scotland and it's very important that continues.
"Very often we take things for granted because it happens to be on our doorstep.
"Certainly, [Scottish independence] could present an opportunity."
Of course, this virtually invisible Irish border is still controversial.
For some, it means extra costs and bureaucracy, but for others it has provided an economic boost.
That is all food for thought for people in the North East and Cumbria pondering that big Scottish vote in September.
There will be a full report on Sunday Politics North East & Cumbria at 11.15 BST this Sunday.