The 28th Dublin City Marathon gets under way this morning with an elite women's race heading the field for the first time.
The marathon will begin at 8.45am with the "elite ladies", including last year's champion Alina Ivanova of Russia, as well as Lezan Kimutai from Kenya, who won in 2004, and Larisa Zyusko from Russia, who finished in third place in 2006.
Wheelchair athletes will begin their race at 9.05am and "elite men" and the rest of the entrants will begin at 9.10am.
Entries to the race have increased by almost 500 on last year, to almost 11,000, with more than half of the participants coming from Ireland.
Among the thousands of participants taking part in the marathon for charity will be stand-up comedian Ed Byrne, who hopes to raise funds for Console, the suicide bereavement and prevention service.
Some 20 asylum seekers will also take part to highlight what they see as the inhumane system of direct provision for asylum seekers in Ireland, which provides bed, food and a weekly allowance of €19.10 while claims for refugee status are being processed.
The participants will wear orange T-shirts with the slogan: "€19.10 a week for asylum seekers = not fair".
Traffic in the city will be halted to accommodate the participants who will run, walk and wheel the circuit from Fitzwilliam Square East to the Phoenix Park and back through Inchicore, to Milltown, finishing on Merrion Square.
Southside drivers will be worst affected again this year.
Dawson Street, Grafton Street, Suffolk Street and Stephen's Green East will be closed from 10am to 5.30pm and Tara Street and Pearse Street will close from 10.30am to 4pm.
Other roads will be closed for shorter periods, including Merrion Row and Baggot Street Lower, from 7.30am to 10.30 am, Mount Street Lower from 8.30am to 10.30am, and Holles Street and Sandwith Street from 8.30am to 9.45am.
Herbert Place and Warrington Place are expected to be closed to traffic from 9.30am to 10.30am and from 6am to 10.30am, Fitzwilliam Street Upper, Fitzwilliam Square, Fitzwilliam Place, Pembroke Street Lower and Pembroke Street Upper will be closed.
AARoadwatch has advised anyone coming from the north or west of the city travelling to events at the RDS to use the East-Link toll bridge and Strand Road or to use the M50/N11. Traffic coming from the south is advised to use the N11 and Ailesbury Road.
Details of the marathon athletes and their finishing times will be available throughout the afternoon on The Irish Timeswebsite at: www.ireland.com