Along the western seaboard, hoteliers, publicans and retailers will baton down the hatches this November as footfall on the streets of their towns slows to a trickle. The tour buses disappear and the tills go quiet as winter moves in. The economic downturn has hit businesses hard in counties such as Mayo, with scores of young people emigrating from sleepy towns and villages in their droves.
As the traditional tourist season ends in September, revenue generation goes with it.
In years gone by, Westport was not immune to the annual downturn. The scenic coastal town has always enjoyed a brisk tourist season, but once the evenings got longer, seasonal staff were let go while others had to cut back their working hours.
In 2010 though, two women devised a plan which has ensured there won't be a free hotel bed to be had on the weekend of November 9 as thousands descend on Westport to run, cycle and climb their way to glory.
The Sea 2 Summit triathlon, now in its fourth year, helps Westport buck the regional trend. The brainchild of Sinead Hopkins and Ciara Joyce, who work in the sales and marketing department of the Westport Plaza and CastleCourt Hotel resort, the event has grown steadily, with local pubs, restaurants and shops benefiting hugely.
"Initially we wanted to fill our hotels at a quiet time of year. November used to be dead, and so we thought, why not try to organise our own triathlon since the Greenway (the longest off-road walking and cycling trail in Ireland) had just been established and Croagh Patrick is so iconic?" says Sinead.
With the Corcoran family, who own the hotels, on board, the idea snowballed.
In 2010, the Sea 2 Summit race attracted 600 entrants – that grew to 1,000 a year later as word of the race spread.
Last year, 1,200 participants registered, and this November, organisers expect 1,500 men and women to don their kit, jump on their bikes and climb the Reeks.
"It's amazing how successful it's become. Already all the 250 rooms in our resort are booked up.
"In total, you'd have 1,100 rooms in Westport, and every last one of them will be full between athletes and their families," explains Sinead.
Competitors will flock to the scenic west Mayo town from all across the country as well as from England and France.
"The buzz around the town that weekend is simply amazing. The pubs will be full and restaurants and shops will see a roaring trade."
Given the influx, it's fair to say the Sea 2 Summit triathlon generates hundreds of thousands of euro for Westport at a time of year when neighbouring urban centres are forced to drastically reduce rates.
"It's difficult to put a figure on exactly how much revenue is generated within the town. Things like spinning classes have really taken off because of it. There are three or four businesses running them throughout the winter. They may have started off as a way of preparing people for the event but they were kept on long after.
"Also, competitors want all the gear, so everything from specific footwear to the bicycles, which can cost €1,000 on average, will be purchased locally.
"Because of the value of the bikes, we have to hire security staff to mind them on the night before the race," explains Sinead.
Down at the nearby Roman Island, I catch up with race competitors Jimmy and Phil Lawlor and race director Paul O'Brien as they get in a spot of training.
One of Paul's key roles is deciding on the course for the event. Triathletes opt for the Supreme race over 56km, but the majority of entrants take part in the more leisurely, but still gruelling, 27km challenge.
"We haven't made any changes really because people want to beat their times," says the former marathon runner who runs his own 'Bootcamp West' business.
"The race starts in town and on along the Greenway. Then competitors jump on a bike at Roman Island before a cycle to Croagh Patrick. In the Supreme race, they go to the summit, while in the shorter one, it's a hike up to the shoulder of the mountain. They must overcome an obstacle race before crossing the finishing line in Westport."
For 46-year-old artist Jimmy Lawlor, originally from Wexford, participation in the Sea 2 Summit race has been life-changing.
"A few years ago, I decided to get fit and started entering triathlons. Now my wife Phil and I are out running or cycling most days. Westport has been transformed because of this race. You see people out training constantly. It leads to such improved health and positivity, it's wonderful for the town."
Phil explains that those of more limited fitness also enjoy the event. "I did it about two years ago and didn't train for it. I brought a picnic up the mountain. You can stop and chat to people, it's all very personal and people have their own individual reasons for doing it."
The adventure race model has since been recreated in rural areas such as Skibbereen in Cork and Portmagee in Kerry.
At Westport's Clew Bay cycle hire shop, Canadian owner Travis Zeray tells me all of his bikes will be snapped up that weekend.
"Between competitors and their families, all of our 400 bikes will be hired out. Our mechanics come in the day before and work all night to make sure the hybrid bikes are in pristine condition. It's a great boost in what would have been a quiet time of the year."
And at the Helm pub and guesthouse, rooms for this year's event were booked since last November.
"We have nine apartments here with 24 rooms. A lot of the people who are staying with us this year would have booked after finishing the race last year. They loved it so much they wanted to make sure they had their accommodation sorted well in advance," explains manager Shane Keogh.
He adds: "By now I suppose we could claim to be the fittest town in Ireland."
More well-known for his singing and rugby exploits, Niall 'Bressie' Breslin will compete in the Supreme race this year in a bid to fundraise for the LARRC cancer support centre near Mullingar.
It's hoped that at least €20,000 will go to what is the only such support centre in Ireland.
In 2012, the event raised €13,000 for the cardiac unit in Crumlin's Children's Hospital.
Also competing this year in the relay section will be world race walking champion Rob Heffernan as well as Irish international athlete turned chef David Gillick and Ironman and fitness fanatic Paul Byrne.
It had been hoped that local GAA hero Lee Keegan, who shone as Mayo reached their second All-Ireland final in two years, would compete, but the night before he's up for what would be his second All-Star, and so will be attending that awards ceremony.
To find out more about the event, visit www.westportsea2summit.ie, or if you wish to donate to the LARCC centre, visit www.larcc.ie