Here's everything you need to know about the Dublin Marathon
Good causes will be the biggest winners as almost 20,000 line up for annual race
They're tapering down and fuelling up for a gruelling slog like no other in sport - but even a marathon isn't enough for some doing it all in the name of charity.
Almost 20,000 will tear up the streets of the capital as the Dublin City Marathon takes place on a Sunday for the first time. What makes it even more special are the vast numbers coming from abroad for what is an ever-growing autumn run.
Organisers say that of the 19,500 participants, more than 13,000 will be from Ireland, but some 5,700 are internationals.
The vast numbers mean there will be several different start times and 39 different pace-setters will help participants ranging in finish times of between three and five hours.
Though for some, three hours just doesn't feel like enough - particularly when there's charity fundraising on the line.
Terry Hughes (37) will have run five marathons in five days by tomorrow afternoon when he crosses the line in Dublin.
Father-of-three and filling station owner Terry left his hometown of Ballyshannon in Co Donegal on Wednesday and ran a marathon to Florencecourt in Co Fermanagh.
On Thursday, he ran from Florencecourt to Cavan. Yesterday, he ran from Cavan to Kells and today he will run to Dunboyne. He will run his fifth marathon through Dublin.
He is raising funds for the Jack and Jill Foundation.
"I only ran one marathon in my life before starting my five marathons on Wednesday," said Terry.
"The toughest section so far was an uphill seven or eight miles from Belturbet to Cavan. But the support has been great," he said.
And then there is Carlow man Paul Ward, a chef by trade who also runs a full-time bootcamp.
Paul and colleagues have already raised €5,000 for regional youth services in Carlow, with another 70 sponsorship cards still to come back. But his challenge this time around might just be his greatest yet.
He's set to leave Carlow at 3.30am by bicycle, complete the marathon and then cycle back home again.
"We'll pull into St Stephen's Green at around 6.30am, we'll put the bikes into the back of one of the support vehicles, get changed and get breakfast at 7.30am," Paul said.
"We'll then make our way over to the start line, get stretched and warmed up, get the marathon done and then I will pull off at half two and cycle back to Carlow - about 85-90km," he added.
Meanwhile, Lucan lad James Casserly (10) and teammate Mark Lacey have raised €40,000 for Barretstown with the Team James campaign.
James is wheelchair-bound and Mark will run the marathon with him, with the pair hoping to complete the course in three hours and 40 minutes.
James has cerebral palsy, which affects his lower limbs and core.
Mark, who has competed in more than 60 marathons, said: "We get to the start line and we'll go off with the elite wheelchairs," he said.
"The plan is to go out and break a record for anyone that's been push-assisted in a marathon in Ireland," he added.
Students at St David's Boys National School in Artane, Dublin, have come together - all 300 of them - to complete a relay marathon and a bit more.
Principal Dwain Moore said the pupils completed a relay marathon on Thursday to raise funds for school improvements.
"We do it as a fundraiser for the school every year.
"We set up a relay marathon, so every child in the school ran a certain distance. We added up the distances covered by everybody and it ended up as 23 marathons," he added.
Travel chaos in capital as marathon fever kicks in
There will be traffic chaos in the capital this weekend - as the Dublin City Marathon gets up and running tomorrow for the first time.
Road closures and disruptions began last night, with event organisers putting barriers in place across the city for the bank holiday weekend.
The course takes in all four Dublin council zones but it will be the city centre that will bear the brunt of the disruption.
Merrion Square North, where the finish line will be, has been closed off to traffic since 7pm on Friday night. It will remain shut until 6pm on Monday night.
While the east and south sides of the square have been out of bounds for drivers since 6am this morning.
When it comes to public transport, Dublin Bus are advising customers their real time bus information system will be out of service on the day.
More than 20 routes will also be affected by the marathon.
The company said in a statement that all diversions are from first bus until roads are reopened by gardaí, unless otherwise stated in their route diversion.
There will be no notable disruption to Luas services on the day.
The company say that they will be operating a regular Sunday service, with trams starting at 7am, finishing at 11.30pm and running every 10 minutes.
Those using Dublin Bikes this weekend have also been warned that stations at Merrion Square and Fitzwilliam Square will be closed all weekend.
Race participants looking to drive into the city on the morning of the race have been told they can avail of discount car parking in the centre.
Q-Park Ireland are offering all race participants and supporters 3pc off throughout the bank holiday weekend at their two main Dublin City car parks.