Cast your memory back a decade and you might recall four-mile tailbacks from Newry to the border.
Once in the city, shelves were picked clean almost as soon as they had been stocked with everything from alcohol to electronics and washing powder.
Favourable exchange rates, the Republic of Ireland's economy in near freefall and the provision of a new motorway made the frontier town the number one retail destination on the island of Ireland.
Today things have changed.
Newry has broadened its base - with the city now arguably as well known for IT firms such as First Derivatives and Statsports as it is for its retail offering.
But the city remains a major draw for shoppers - especially at Christmas.
In 1984 a strike by Irish customs officials led to a very merry Christmas for some shoppers south of the border 🛍️ pic.twitter.com/uyjjZRQ6Cd— BBC Northern Ireland (@BBCnireland) December 22, 2019
According to Eamonn Connolly, who runs Newry Business Improvement District, the city has adapted its offer to remain relevant.
'Emergence of a more sophisticated shopper'
"Exchange rate is still the major driver," he says.
"And obviously sterling has appreciated a little with the added certainty around Brexit but cross-border trade is still fairly constant.
"What we are seeing is the emergence of a more sophisticated shopper coming up - buy what they want rather than buying everything.
"Its goods, its services. We are seeing a massive growth in professional services - dentistry, opticians. Things where there's a marked price differential north-south."
Mr Connolly said up to 20% of spaces in the city's main retail hubs are filled with Republic of Ireland number plates, compared to about 10% of those in Dundalk being filled with Northern Ireland plates.
On our own cross-border shopping trip we found cheaper toys, groceries and alcohol in Newry but cheaper fuel and games consoles in Dundalk.
But there are other factors at play in the battle to attract and retain business on the border.
Paddy Malone of Dundalk Chamber of Commerce believes the north Louth town is experiencing its best Christmas in 20 years.
This, in part, he puts down to local people starting to feel benefits of the much trumpeted recovery of the economy - in part exemplified by the ongoing build of a €325m WuXi Biologics facility in the town.
He also believes the Chamber of Commerce's ability to take advantage of a generous tax break initiative is proving beneficial.
"An employer can give up to €500 to a member of staff tax free once a year - but not in cash, in a voucher. So we have created a series of vouchers.
"We meet the administration costs and everything else so there is no extra cost to the employer.
"Over the last couple of years we've sold around €2.6m worth of vouchers and we're hopeful this year we'll get to the €3m. And there's obviously the multiplier effect of that.
"There are 330 local shops that will accept these. So there is more employment being generated - mostly for young people who will then spend it in the town at the weekends.
"It is everything from supermarkets, toy stores, off-licences so virtually everything you would be buying at this time of year.
"We've lived with currency fluctuations since 1979.
"We are efficient and our shopkeepers have to be that little bit more clever because we have to compete with Newry but obviously they also have to cope with challenges as well."