More than 10,500 runners will compete in the 25th Dublin City Marathon on Monday.
The near-record turnout - the first marathon attracted a field of just over 2,000 runners in 1979 - features a strong entry from the United States and Canada.
Organisers say the race will bring up to 20,000 people, including runners and their friends, into the city for the weekend. The value of their custom is estimated at €12 million.
They rejected criticism of the fees charged for this year's race, which have increased by more than 70 per cent on last year for some participants.
Last year's fees varied from €30 for Irish runners to €50 for overseas entrants. This year, fees for all EU runners were set at €50, while late entrants and non-EU applications were charged €70. A further €7 was charged for handling Internet/credit card payments.
Last night a spokeswoman said the EU Commission had told organisers they could not charge differential fees to entrants from different EU member-states.
In addition, runners were being provided with a timing chip this year. Although the chips had to be returned after the race, their rental involved considerable expense, she explained.
Adidas is the main sponsor, but most of its support is given in kind, in the form of T-shirts, blankets and jackets for more than 700 stewards.
Runners from 64 countries are taking part in Monday's race, which starts at 9 a.m. in Nassau Street (wheelchair athletes start five minutes earlier).
The course, which is substantially the same as last year, leads over O'Connell Bridge and then follows a 26.2-mile route on both sides of the Liffey. The finish is at Merrion Square West.
The race director, Mr Jim Aughney, described the resurgence in entries as "incredible".
"Early entries were way up on the last few years, but based on the entry numbers we would normally receive in the last few weeks, we really did not expect to meet our target.
"We are obviously delighted to finally break the 10,000 mark again, particularly in our 25th anniversary year," he said.
Thirty-four runners have completed every Dublin Marathon to date, 33 men and one woman, Ms Mary Nolan Hickey.
Among the elite runners in this year's race is South Africa's Zacharia Mpolokeng, who won in 2001 and finished 3rd in 2002.
The women's record has been smashed in the last two marathons, and yet again the women's field looks set to hold a new record-breaker.
Florence Barosio, a sister of the famous Kenyan marathon runner, Sally Barosio, is one of the favourites. She holds a personal best of 2:27:00 from New York in 2000.