The annual Dublin Marathon took place on Sunday, October 29th, 2023, and several roads were closed as a result of the event. Most of the closures were lifted by 5 pm on the same day, but certain parts of Merrion Square remained closed until Monday, October 30th. Merrion Square North was closed until 4 pm on Monday, while Merrion Square South remained closed until 8 pm on Sunday, and a handful of other streets remained closed until 7:30 pm on Sunday. The following roads were closed for the marathon:

• Leeson Street Lower
• Stephen Green South
• Cuffe Street
• Kevin Street Lower
• Kevin Street Upper
• Patrick Street
• Nicholas Street
• High Street
• Bridge Street
• Ushers Quay
• Victoria Quay
• Parkgate Street
• Conyngham Road
• North Wall Quay
• Guild Street
• Sheriff Street Upper
• East Wall Road
• North Strand Road
• Annesley Bridge Road
• Fairview Strand
• North Strand Road
• Clontarf Road
• Alfie Byrne Road
• Mount Prospect Avenue
• Nutley Lane (Water Station)
• Merrion Road (Inbound Only)
• Northumberland Road
• Mount Street Lower

The start of the marathon was at Fitzwilliam Street Upper, and the finish was at Merrion Square North. The marathon route passed through several areas of Dublin, including St. Stephens Green, Phoenix Park, Chapelizod, Inchicore, Dolphins Barn, Crumlin, Terenure, Busky Park, and UCD before turning back towards the city center and finishing in Merrion Square North, close to Trinity College Dublin. The road closures caused some disruptions to public transport services, including Dublin Bus and Irish Rail.