Clew Bay Half Marathon
Louisburgh, Mayo
12 Sep 2026
⚠ Start times change frequently. Always check with race organiser or their website for this year's confirmed start time before travelling.
Course map
Map based on 2025 route
⚠ This map is for indicative purposes only — routes can change, or be reversed, year to year. Check with the race organiser for this year's confirmed map.
Elevation profile
About this race
The Clew Bay Half Marathon is a challenging and scenic rural one-lap course that starts and finishes in Louisburgh, Co. Mayo. The course takes runners on winding, rolling roads along the stunning Atlantic coastline, passing landmarks like a 2,200-year-old Dolmen and offering views of Clare Island and Croagh Patrick.
Course profile & record eligibility
World Athletics record-eligibility rules cap net elevation loss at 1m per km of race distance, and require the start and finish to be no more than 50% of the race distance apart — both meant to stop a course gaining an unfair edge from downhill grade or a point-to-point tailwind. This is based on this course's recorded elevation and GPS data, not an official measurement or certification.