The Carlingford ferry, which connects Northern Ireland to the Republic of Ireland, was launched one year ago but is already facing an uncertain future with a solution to the post-Brexit border problem still to be found.
The service has proved popular with commuters looking for a speedy crossing to work, but the potential imposition of time-consuming customs checks means it may be increasingly reliant on an underdeveloped tourism sector.
The project was ten years in the making when Britain voted in 2016 to leave the European Union, but despite the setback, Frazer Ferries, which operates the service, has vowed to plough on.
"There is no clearly defined endgame for Brexit yet and we don't know what it will ultimately look like, but we do feel very confident that we will adapt," Paul O'Sullivan, director of Frazer Ferries, told AFP.
Barry Gardener and his wife Rita were among those at Carlingford quay on a cool and calm weekday morning, waiting with two other vehicles to board the ferry.
The couple were travelling from Drogheda, 65 kilometres (40 miles) to the south, for a day's shopping in Newcastle, across the border in Northern Ireland.
"I decided to take her out of the country," joked the mischievous 70-year-old, as his wife laughed, holding onto his arm.
The service, which can accomodate 10 cars, runs every 30 minutes across the Carlingford lough, an inlet of the Irish Sea that separates the two countries.
There are no checks on the border between the British province of Northern Ireland and its southern neighbour, as both are currently members of the European Union and share the same customs rules.
But EU and British negotiators are so-far stumped on how to maintain the open border post-Brexit.
The quiet region around the lough is renowned for its idyllic, mountainous scenery, but remains isolated, and is more than 20km from the M1 motorway linking Dublin to Belfast.
"A lot of people didn't know this part of the world existed," said Geoffrey Chestnutt, owner of a holiday resort on the Northern Irish coast, noting that the ferry had boosted business.
"They would have travelled directly from Newry (in Northern Ireland) to Newcastle, just missing it out," added the 40-year-old. "It's a good thing for both sides of the lough".
- 'Neglect' -
In addition to the 17 jobs directly created by the service, it also has the potential to provide a broader boost to the economy, said O'Sullivan.
The operator said a fishery based in the Northern Ireland coastal town of Kilkeel had been in touch about the possibility of making deliveries to the south.
"The ferry would obviously cut a 30 mile journey down to a couple of miles," he said, explaining that the boat takes quarter-of-an-hour, compared with more than an hour by road.
Ticket-seller Nora McKee, wrapped up in her blue raincoat emblazoned with the company logo, told AFP that "most of our commuters are from the north side -- a whole lot is travelling through to Dublin for work."
But the return of a physical border could spell an end to the shortened journey for professional clientele.
The ferry is already trying to increase its tourist numbers, but the holidaymakers are still few and far between, according to the moustachioed Brian Mac An Bhaird, who blames a lack of investment.
"Look at today, this is the middle of the summer... there are no people. Where are the tourists?" asked the 71-year-old retiree, noting that "you can't even get a sandwich here".
Paddy Malone, from the regional chamber of commerce, said Carlingford was hit particularly hard by the Troubles, and has "been neglected" since peace was achieved.
He partly blames authorities south of the border, whom he said "feel that if they get people up to the border, half of the money will be spent on the other side".
Malone believes the area has "huge potential if we can manage Brexit", but admitted that uncertainty hung over the border region and the future of the ferry.
On a more optimistic note, O'Sullivan insisted that if a physical border reappeared, "perhaps those cars would rather wait for these checks in the comfort of the ferry terminal overlooking Carlingford Lough" than take the motorway.
Cattle stand close to the border between Newry in Northern Ireland and Dundalk in the Republic of Ireland
There are no checks on the border between the British province of Northern Ireland and its southern neighbour