The British racing year has a shape most runners know without being told: spring marathons, a quiet hot summer, autumn halves, cross country and hibernation. Ireland's is different, and the difference comes straight out of the climate — an 11°C annual temperature range means there is no month you cannot race in, so the calendar simply does not stop.
January and February: the imperial classics
Where a British club would be doing cross country and not much else, the Irish season opens with serious road racing at imperial distances. This is the most distinctive thing about the calendar here and the part visitors never expect.
- Raheny 5, in north Dublin in late January, draws around 3,500 runners and starts at three in the afternoon — a deliberate choice that makes a January race genuinely raceable.
- Trim 10, in the Boyne Valley at the end of January or start of February, at noon.
- The John Treacy Dungarvan 10 in early February, named for the Waterford man who took Olympic marathon silver in 1984, and now the spring ten-miler that Irish clubs build around.
That imperial bias is worth understanding. Ireland races 5 and 10 miles far more than Britain does, and a ten-mile time in February is how a great many Irish runners set their target for the year. If you are visiting in winter, these are the races to look for — not the 10Ks.
March to May: the halves, and the first marathons
Spring is half marathon season. Bohermeen in Meath in early March is the established early fixture; Westport, Wexford and Longford follow through April; Connemara arrives at the end of April and is a different proposition entirely.
The first marathon of the year is Limerick on the May bank holiday weekend, followed by the Clare Burren Marathon Challenge across the limestone in late May. Neither is a fast course, and neither pretends to be.
The one to know about
The Connemarathon at the end of April is the race visitors most often travel for, and the one they most often underestimate. It runs on exposed mountain road through the Inagh valley and finishes with a sustained climb known locally as the Hell of the West. Almost nobody runs a personal best there, and that is the point of it.
June to August: marathons, and the west
This is where Ireland diverges most sharply from Britain. Where British marathons vacate high summer, Ireland runs Cork City in early June and Dingle in early September, and the reason is simply that it does not get hot enough to matter — a July high of 19.3°C in Dublin against 22.8°C in London.
Summer is also when the west coast calendar comes alive: the Streets of Galway 8K on an August Saturday evening during Race Week, the Achill half on the Mayo coast, the Dingle races on the Slea Head road. These are the races people plan holidays around, and they are all fundamentally wind races.
September and October: the peak
September is the fastest month in the Irish calendar. Charleville, in north Cork, bills itself as the flattest and straightest half marathon in Ireland and is where Irish runners go for a half-marathon personal best. Run Galway Bay and the Athlone half sit in the same window.
The year finishes with the Dublin Marathon on the last Monday of October — the October bank holiday, a public holiday in Ireland, which keeps the city quiet for the closures while the crowds are still out. It is a ballot, heavily oversubscribed against a field of around 20,000, and it is the single biggest event in Irish running.
Cork City moved to a ballot for 2027 as well, covering the marathon, half and 10K alike. Between them, the two largest Irish marathons are now both lotteries rather than sales, which is a real change in how you plan a year here.
The Dublin Race Series
One structure worth knowing about specifically. The Dublin Marathon organisation runs three build-up races across the summer, all in or around Phoenix Park, and a large share of the marathon field enters all three:
- 1 The Fingal 10K in July, in north County Dublin.
- 2 The Frank Duffy 10 Mile in August, starting on Chesterfield Avenue in Phoenix Park and finishing on Furze Road.
- 3 The Dublin Half Marathon in September, six weeks out from the marathon.
It is a well-built progression — 10K, then 10 miles, then a half, each roughly a month apart and landing exactly where a marathon block wants them. A ten-mile time in August is the single best predictor of both the September half and the October marathon, and the series exists to give you one.
Where the ultras sit
The Irish ultra calendar has its own shape. It opens in January with the Art O'Neill Challenge, a 62km night race from Dublin Castle over the Wicklow mountains that retraces a 1592 winter escape — as much re-enactment as race. Donadea 50K in February is the flat, fast, lapped forest counterpart and the country's standard entry-level ultra.
From there it climbs: the Maurice Mullins over the northern Wicklow Way in March, the Connemara Ultra in April, the Wicklow Way Race across the full 127km trail in July, and the Kerry Way Ultra's 200km circuit of the Ring of Kerry on the first weekend of September.
And every Saturday
There are 114 parkruns in the Republic across all 26 counties, from 26 in Dublin down to one in Carlow. Free, weekly, timed and 5K, and for most Irish runners the fixed point the rest of the calendar is arranged around.