Dublin Marathon 2027 : the course km by km, race week and travel

Dublin’s difficulty sits in the first half. The loop climbs 141.9 m in all, and 66.6 m of that comes in the opening 11.3 km, on the way out to and across Phoenix Park. The second half has one well-known hill, near km 35, and two long descents either side of it, and it ends 3 m lower than it started. A runner who keeps something back for the first 11 km gets most of the climbing over while still fresh, and has the drop through Milltown and the last 4 km off Heartbreak Hill to run.

The course is one loop through the city, its northwest and its southern suburbs, starting on Leeson Street Lower and finishing on Mount Street Upper, a few streets apart. The kilometres and heights below are measured along the organiser’s 2026 street list, on Ireland’s lidar elevation model. The organiser has not said whether the 2027 course changes, so check its course page before you plan your pacing.

Km 0 to 2.6: down to the Liffey

The start line is on Leeson Street Lower, about 60 m from St Stephen’s Green, and the organiser calls the start downhill. The road loses 9 m in the first 2.6 km. It rounds the Green, runs along Cuffe Street and Kevin Street into the Liberties, along Patrick Street by St Patrick’s, and past Christ Church Cathedral at about km 1.6 before dropping down Bridge Street to the river. The course crosses the Liffey on O’Donovan Rossa Bridge at about km 2.3, and at about km 2.6 it is at 3.3 m, the lowest point of the whole race.

Km 2.6 to 11.3: the long climb to the high point

From the river the course climbs, with hardly a level stretch, for nearly 9 km. It follows the north quays west (Inns Quay, Arran Quay, Ellis Quay), then turns up Blackhall Place through Stoneybatter, Manor Street and Aughrim Street to the North Circular Road. North Road, Spa Road and Lord’s Walk take it into Phoenix Park, which the organiser places at about km 6, and by then the road is at about 35 m.

Chesterfield Avenue carries the course 3.4 km across the park, from about km 6.6 to km 9.9, past the Phoenix Monument at about km 8.1, and climbs another 20 m on the way. Castleknock Road and College Road then bring the top of the course: 66.7 m at about km 11.3. The average gradient from the Liffey to here is under 1%, so it rarely looks like a hill, but by km 11.3 47% of the race’s climbing is done. Run it on effort rather than on the watch.

Km 11.3 to 17.4: down to Chapelizod and straight back up

The longest descent of the race follows. Tower Road, Knockmaroon Road and Upper Glen Road drop 58.5 m in about 5 km, out through Chapelizod Gate at about km 15.2 and across the Liffey again on Anna Livia Bridge at about km 15.9. The bottom is 8.2 m, at Chapelizod, around km 16.2.

There is no recovery at the bottom. St Laurence’s Road and Sarsfield Road climb 15.3 m in the next 1.2 km, to 23.5 m by about km 17.4. At about 1.3% that is a steeper average than Heartbreak Hill, and it comes straight after a long downhill, when the legs least expect it.

Km 17.4 to 20.4: Kilmainham and the South Circular

Inchicore Road passes Kilmainham Gaol at about km 18.6, and the South Circular Road runs nearly level to Dolphin’s Barn at about km 20.4. These 3 km climb only 2 m, and they are the place to settle before halfway.

Km 20.4 to 27.5: halfway and the long drag south

Halfway falls on Crumlin Road, which climbs 20 m between about km 20.6 and km 22.3. The road keeps rising, more gently, along Drimnagh Road, Walkinstown Road, Cromwellsfort Road, Kimmage Road West and Fortfield Road, another 10 m to 50.2 m at about km 27.5. That is the highest ground of the second half.

Km 27.5 to 33: Terenure and Milltown, downhill

Templeogue Road, Terenure Road East, Orwell Road, Orwell Park, Dartry Road and Milltown Road fall 31 m in about 5 km, to 18.8 m at about km 33.0 on Clonskeagh Road. This is the first long descent of the back half, and the place where a runner who saved something early can start to use it.

Km 33 to 35.4: Heartbreak Hill

Clonskeagh Road and Roebuck Road climb 19.2 m in 2.4 km, from about km 33.0 to 38.0 m at about km 35.4. The organiser calls it the Irish Heartbreak Hill. By the numbers it is about 0.8% on average, gentler than the climb out of Chapelizod. It hurts because it arrives at km 33, and because it is the last one.

Km 35.4 to the finish: down to the sea and in

From the top, Foster’s Avenue and Stillorgan Road lead over the UCD Flyover at about km 37.4 and into Nutley Lane, which the organiser marks by RTÉ at about km 38. The road loses 34.6 m between km 35.4 and about km 39.2, where Merrion Road is at 3.4 m. Merrion Road passes the RDS at about km 40.5, and the course crosses Ball’s Bridge at about km 40.6, then runs along Pembroke Road and Northumberland Road, over McKenny’s Bridge at about km 41.7, and along Warrington Place. It rounds the Pepper Canister Church on Mount Street Crescent, and the line is on Mount Street Upper, about 94 m beyond the church. The last 3 km climb 6.2 m in total.

The organiser’s spectator points at the finish are on Herbert Street, Stephen’s Lane, Power’s Court and Mount Street Crescent.

The race-week details for 2027 are not out yet. This is how race week ran in 2026, from the 2026 Final Instructions and the organiser’s race-day pages. Check them again for 2027.

The expo and your race number

Numbers were collected at the expo at the RDS Simmonscourt in Ballsbridge, open from 12 noon to 7pm on the Friday and 9am to 6pm on the Saturday. Bring the e-ticket emailed to you, which shows your wave, and photo ID, such as a passport or a driving licence. The organiser asks every runner to collect their own number in person, and collection closes at 6pm on the Saturday, so a Sunday-morning arrival in Dublin means no race. The timing chip is on the back of the number, and the back also has space for your medical details. The expo is also where you can meet the pacers, and where you get the clear plastic bag you will need for the bag drop.

On the Saturday morning in 2026 there was a 5 km shakeout run in Phoenix Park at 9am, a paid extra at EUR 20.

Waves and the start

Waves are allocated on the finish time you gave when you entered, and in 2026 no wave changes were allowed. The colour of your number is your wave. The 2026 start times were:

• Wheelchair: 8.40am
• Wave 1 (orange): 8.45am
• Wave 2 (green): 9.05am
• Wave 3 (blue): 9.25am
• Wave 4 (purple): 9.45am

The organiser asked runners to arrive by 8am and to be in their start zone by 8.30am, and said the wave times may change.

Bag drop

Four baggage areas, one per wave colour, sat on Merrion Square North, a short walk from the start. Only the clear plastic bag handed out at the expo is accepted, and every bag is checked. In 2026 they opened and closed by wave: orange 7.15 to 8am, green 7.35 to 8.20am, blue 7.55 to 8.40am and purple 8.05 to 9am. The family meeting area after the race is next to the baggage areas at Lincoln Place.

The cut-off

The course stays open for seven hours from the moment the last runner crosses the start line. Anyone still out after that is asked to move onto the footpath so the roads can reopen. With the last wave off at 9.45am, even a runner in wave 4 has the full seven hours.